MONTREAL PROTOCOL 

ON SUBSTANCES THAT DEPLETE 

THE OZONE LAYER 

UNEP

2010 REPORT OF THE

REFRIGERATION, AIR CONDITIONING AND HEAT PUMPS

TECHNICAL OPTIONS COMMITTEE

2010 Assessment

UNEP 

2010 REPORT OF THE

REFRIGERATION, AIR CONDITIONING AND HEAT PUMPS

TECHNICAL OPTIONS COMMITTEE

2010 ASSESSMENT
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report iv 

Montreal Protocol 

On Substances that Deplete the Ozone Layer

UNEP 

2010 REPORT OF THE

REFRIGERATION, AIR CONDITIONING AND HEAT PUMPS

TECHNICAL OPTIONS COMMITTEE

2010 ASSESSMENT

The text of this report is composed in Times New Roman. 

Co-ordination: Refrigeration, Air Conditioning and Heat 

 Pumps Technical Options Committee

Composition: Lambert Kuijpers (Co-chair) 

Formatting, Reproduction: UNEP Nairobi, Ozone Secretariat 

Date: February 2011 

No copyright involved 

Printed in Kenya; 2011 

ISBN 978-9966-20-002-0
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report v

DISCLAIMER 

The United Nations Environment Programme (UNEP), the Technology and Economic Assessment Panel 

(TEAP) co-chairs and members, the Refrigeration AC and Heat Pumps Technical Options Committee, cochairs and members, and the companies and organisations that employ them do not endorse the performance, 

worker safety, or environmental acceptability of any of the technical options discussed. Every industrial 

operation requires consideration of worker safety and proper disposal of contaminants and waste products. 

Moreover, as work continues - including additional toxicity evaluation - more information on health, 

environmental and safety effects of alternatives and replacements will become available for use in selecting 

among the options discussed in this document. 

UNEP, the TEAP co-chairs and members, the Refrigeration, AC and Heat Pumps Technical Options 

Committee, co-chairs and members, in furnishing or distributing this information, do not make any warranty 

or representation, either express or implied, with respect to the accuracy, completeness, or utility; nor do they 

assume any liability of any kind whatsoever resulting from the use or reliance upon any information, material, 

or procedure contained herein, including but not limited to any claims regarding health, safety, environmental 

effect or fate, efficacy, or performance, made by the source of information. 

Mention of any company, association, or product in this document is for information purposes only and does 

not constitute a recommendation of any such company, association, or product, either express or implied by 

UNEP, the Technology and Economic Assessment Panel co-chairs or members, the Refrigeration, AC and 

Heat Pumps Technical Options Committee co-chairs or members, or the companies or organisations that 

employ them. 

ACKNOWLEDGEMENT 

The UNEP Refrigeration, A/C and Heat Pumps Technical Options Committee acknowledges with thanks the 

outstanding contributions from all of the individuals and organisations who provided technical support to 

committee members. In developing this report, particularly the chapter lead authors were instrumental. 

The names of chapter lead authors, co-authors and contributors are given at the start of each chapter. Addresses 

and contact numbers of the chapter lead authors and all other authors of the UNEP TOC Refrigeration, A/C and 

Heat Pumps can be found in Annex I. 

The opinions expressed are those of the Committee and do not necessarily reflect the views of any sponsoring or 

supporting organisations. 

Gratitude is expressed to UNEP’s Ozone Secretariat, Nairobi, Kenya for the co-operation in formatting and 

styling of the report and for the reproduction of this report. 

2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report vii

UNEP 

2010 REPORT OF THE

REFRIGERATION, AIR CONDITIONING AND HEAT PUMPS

TECHNICAL OPTIONS COMMITTEE

2010 ASSESSMENT

Table of Contents 

KEY MESSAGES ......................................................................................................................................XII 

ABSTRACT EXECUTIVE SUMMARY.....................................................................................................1 

EXECUTIVE SUMMARIES OF ALL CHAPTERS..................................................................................5 

1 INTRODUCTION ..............................................................................................................................16 

1.1 MONTREAL PROTOCOL DEVELOPMENTS ..........................................................................................16 

1.2 THE UNEP TECHNOLOGY AND ECONOMIC ASSESSMENT PANEL......................................................20 

1.3 THE TECHNICAL OPTIONS COMMITTEE REFRIGERATION, A/C AND HEAT PUMPS.............................22 

1.4 REFRIGERATION, AIR CONDITIONING AND HEAT PUMPS ..................................................................24 

1.4.1 General Remarks....................................................................................................................24 

1.4.2 Long Term Options and Energy Efficiency ............................................................................25 

1.4.3 Set up of the 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report.................27 

2 REFRIGERANTS ..............................................................................................................................30 

2.1 INTRODUCTION .................................................................................................................................30 

2.1.1 Refrigerant Progression.........................................................................................................30 

2.1.2 Unsaturated Hydrofluorochemicals.......................................................................................31

2.2 DATA SUMMARY ..............................................................................................................................31 

2.2.1 Ozone Depletion Potentials....................................................................................................38 

2.2.2 ODP and GWP Data for Regulatory and Reporting Purposes..............................................38 

2.3 STATUS AND RESEARCH NEEDS FOR DATA.......................................................................................40 

2.3.1 Thermophysical Properties ....................................................................................................40 

2.3.2 Heat Transfer and Compatibility Data ..................................................................................40 

2.3.3 Safety Data.............................................................................................................................42 

2.4 REFERENCES.....................................................................................................................................43 

3 DOMESTIC REFRIGERATION .....................................................................................................50

3.1 INTRODUCTION .................................................................................................................................50 

3.2 OPTIONS FOR NEW EQUIPMENT ........................................................................................................50 

3.2.1 Refrigerant Options................................................................................................................51 

3.2.2 Not-In-Kind Alternative Technologies ...................................................................................52

3.2.3 Product Energy Efficiency Improvement Technologies .........................................................53 

3.3 OPTIONS FOR EXISTING EQUIPMENT.................................................................................................54 

3.3.1 Drop-In Conversion of In-Service Products ..........................................................................54 

3.4 END-OF-LIFE CONSERVATION AND CONTAINMENT CONCERNS ........................................................55 

3.5 CURRENT REFRIGERANT USE ...........................................................................................................55 

3.5.1 New Equipment Production ...................................................................................................55 

3.5.2 Field Service...........................................................................................................................56 

3.5.3 Future Refrigerant Demand Implications ..............................................................................57 

3.5.4 Future Refrigerant Emission Implications .............................................................................57 

3.6 REFERENCES.....................................................................................................................................58 
viii 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

4 COMMERCIAL REFRIGERATION..............................................................................................60 

4.1 INTRODUCTION .................................................................................................................................60 

4.2 APPLICATION....................................................................................................................................60 

4.2.1 Equipment and Systems..........................................................................................................60 

4.3 OPTIONS FOR NEW EQUIPMENT ........................................................................................................62 

4.3.1 Stand-Alone Equipment..........................................................................................................62 

4.3.2 Condensing Unit Systems.......................................................................................................65 

4.3.3 Supermarket Systems..............................................................................................................65 

4.5 OPTIONS FOR EXISTING EQUIPMENT.................................................................................................70 

4.9 REFERENCES.....................................................................................................................................72 

5 INDUSTRIAL SYSTEMS .................................................................................................................76 

5.1 INTRODUCTION .................................................................................................................................76 

5.2 APPLICATIONS (INCLUDING SIZE OF MARKET, CURRENT PRACTICE, REGIONAL VARIATIONS)............80 

5.2.1 Food Processing.....................................................................................................................80 

5.2.2 Cold Storage...........................................................................................................................80 

5.2.3 Industrial Cooling in Buildings and IT Centres.....................................................................81 

5.2.4 Industrial Heat Pumps and Heat Recovery............................................................................81 

5.2.5 Leisure....................................................................................................................................82 

5.2.6 Process Refrigeration.............................................................................................................82 

5.3 WORKING FLUID OPTIONS FOR NEW EQUIPMENT.............................................................................82 

5.3.1 R-717 (Ammonia) ...................................................................................................................82 

5.3.2 Hydrofluorocarbons...............................................................................................................83 

5.3.3 HCFC-22................................................................................................................................84 

5.3.4 Hydrocarbons.........................................................................................................................84 

5.3.5 R-744 (Carbon dioxide) .........................................................................................................84 

5.3.6 R-718 (Water).........................................................................................................................84 

5.3.7 Absorption..............................................................................................................................85 

5.4 RETROFIT OPTIONS FOR EXISTING EQUIPMENT ................................................................................85 

5.4.1 Conversion to HFC Blends ....................................................................................................85 

5.4.2 Conversion to R-744 ..............................................................................................................86 

5.4.3 Conversion to R-717 ..............................................................................................................86 

5.4.4 Conversion to Hydrocarbon...................................................................................................86 

5.5 OVERVIEW OF REFRIGERANT CONSUMPTION, BANKS AND EMISSIONS .............................................86 

5.6 SERVICE REQUIREMENTS..................................................................................................................88 

5.7 REFERENCES.....................................................................................................................................88 

6 TRANSPORT REFRIGERATION ..................................................................................................92 

6.1 INTRODUCTION .................................................................................................................................92 

6.2 TECHNICAL PROGRESS......................................................................................................................92 

6.2.1 Merchant, Naval and Fishing Vessels....................................................................................92

6.2.2 Road Transport ......................................................................................................................94 

6.2.3 Railcars ..................................................................................................................................95 

6.2.4 Intermodal Containers ...........................................................................................................96 

6.2.5 Small Containers and Boxes ..................................................................................................97 

6.3 REFRIGERANT OPTIONS FOR EXISTING EQUIPMENT..........................................................................97 

6.4 REFRIGERANT OPTIONS FOR NEW EQUIPMENT .................................................................................98 

6.5 RECOVERY, REUSE AND DESTRUCTIONS OF REFRIGERANTS...........................................................100 

6.6 BANK AND EMISSION DATA............................................................................................................100 

6.7 REFERENCES...................................................................................................................................104 

7 AIR-TO AIR AIR CONDITIONERS AND HEAT PUMPS ........................................................106 

7.1 INTRODUCTION ...............................................................................................................................106 

7.2 APPLICATIONS ................................................................................................................................106 

7.2.1 Small Self-Contained Air Conditioners................................................................................107 

7.2.2 Non-ducted (or duct-free) Split Residential and Commercial Air Conditioners..................107 

7.2.3 Ducted, Split Residential Air Conditioners ..........................................................................108 

7.2.4 Ducted Commercial Split and Packaged Air Conditioners..................................................109 

7.3 CURRENT USE OF HCFC-22 ...........................................................................................................110 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report ix

7.3.1 Small Self-Contained Air Conditioners................................................................................110 

7.3.2 Non-ducted Split Air Conditioners.......................................................................................110 

7.3.3 Ducted, Split Residential Air Conditioners ..........................................................................111 

7.3.4 Ducted Commercial Split and Packaged Air conditioner ....................................................111 

7.3.5 HCFC-22 Bank.....................................................................................................................111 

7.4 OPTIONS FOR NEW EQUIPMENT ......................................................................................................111 

7.4.1 Methodology.........................................................................................................................111 

7.4.2 Single Component HFC Refrigerants...................................................................................112 

7.4.3 HFC Blends..........................................................................................................................112 

7.4.4 Reduced GWP HFC Refrigerants and Blends......................................................................113 

7.4.5 Hydrocarbon Refrigerants ...................................................................................................115 

7.4.6 R-744....................................................................................................................................116 

7.4.7 Flammability Considerations...............................................................................................117 

7.4.8 Not-in-Kind Alternative Technologies..................................................................................117

7.5 OPTIONS FOR EXISTING EQUIPMENT...............................................................................................118 

7.5.1 Service Blend Refrigerants...................................................................................................118 

7.5.2 Retrofit Refrigerants.............................................................................................................119 

7.5.3 Anticipated Market Impact of Drop-in and Retrofit Refrigerants........................................119 

7.5.4 Hydrocarbons as Conversion/Drop-in Refrigerants............................................................119 

7.6 HIGH AMBIENT CONSIDERATIONS ..................................................................................................120 

7.6.1 R-410A in High Ambient Applications .................................................................................120 

7.6.2 HC-290 in High Ambient Applications ................................................................................121 

7.6.3 R-407C in High Ambient Applications.................................................................................121 

7.6.4 HFC-32 in High Ambient Applications................................................................................121 

7.6.5 HFC-134a and HC-600a in High Ambient Applications .....................................................121 

7.6.6 R-744 in High Ambient Applications ...................................................................................122 

7.6.7 HFC Replacements for High Ambient Applications.............................................................122 

7.7 REFERENCES...................................................................................................................................122 

8 WATER HEATING HEAT PUMPS .................................................................................................128 

8.1 INTRODUCTION ...............................................................................................................................128 

8.2 TYPES OF HEAT PUMPS...................................................................................................................128 

8.2.1 Heat Pump Water Heaters (HPWH) ....................................................................................129 

8.2.2 Space Heating Heat Pumps..................................................................................................129 

8.2.3 Combined Space and Hot Water Heat Pumps .....................................................................130 

8.2.4 Capacity Ranges of Water and Space Heating Heat Pumps................................................130 

8.3 HEAT PUMP IMPLICATIONS AND TRENDS........................................................................................130 

8.3.1 Trends of Heat Pumps Replacing From Gas or Fuel Burning System.................................130 

8.3.2 CO2 Heat Pump Water Heaters............................................................................................131 

8.4 CURRENT REFRIGERANT OPTIONS FOR WATER AND SPACE HEATING HEAT PUMPS.......................131 

8.4.1 HCFC-22..............................................................................................................................132 

8.4.2 HFC-134a and HFC blends R-407C and R-410A ...............................................................132 

8.4.3 Hydrocarbons.......................................................................................................................132 

8.4.4 R-744 (Carbon Dioxide).......................................................................................................132 

8.4.5 R-717 (Ammonia) .................................................................................................................133 

8.5 FUTURE REFRIGERANT OPTIONS FOR NEW HEAT PUMPS ...............................................................133 

8.5.1 HFC-134a and HFC Blends R-407C and R-410A...............................................................134 

8.5.2 HFC-32 ................................................................................................................................134 

8.5.3 HFC-1234yf and Other Low-GWP HFC Blends..................................................................134 

8.5.4 R-744 (Carbon Dioxide).......................................................................................................135 

8.5.5 Hydrocarbons.......................................................................................................................135 

8.5.6 R-717 (Ammonia) .................................................................................................................135 

8.6 REFERENCES...................................................................................................................................135 

9 CHILLERS .......................................................................................................................................138 

9.1 FUNCTION OF CHILLERS .................................................................................................................138 

9.2 TYPES OF CHILLERS........................................................................................................................138 

9.2.1 Mechanical Vapour-Compression Chillers..........................................................................138 

9.2.2. Absorption Chillers ..............................................................................................................140 
x 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

9.2.3 Chiller Capacity Ranges ......................................................................................................141 

9.3 DEVELOPMENTS AND TRENDS IN CHILLER MARKETS.....................................................................142 

9.3.1 Measures of Chiller Efficiency or Energy Use.....................................................................142 

9.3.2 Developments in the Market – Vapour-Compression Chillers.............................................143 

9.3.3 Developments in the Market – Absorption Chillers .............................................................144 

9.4 CURRENT REFRIGERANT CHOICES AND OPTIONS FOR MECHANICAL VAPOUR-COMPRESSION CHILLERS

 144 

9.4.1 Positive Displacement Chillers ............................................................................................144 

9.4.2 Centrifugal Chillers..............................................................................................................146 

9.5 REFRIGERANT OPTIONS FOR NEW CHILLER EQUIPMENT ................................................................146 

9.5.1 Options for New Positive Displacement Chillers.................................................................147 

9.5.2 Options for New Centrifugal Chillers ..................................................................................149 

9.5.3 Issues with HCFC-123, HFC-134a, R-410A, and Other HFC Chiller Refrigerants ...........149 

9.5.4 Alternatives to Vapour Compression Systems (Absorption Chillers)...................................150 

9.6 OPTIONS FOR EXISTING CHILLER EQUIPMENT ................................................................................150 

9.6.1 Positive Displacement Chillers ............................................................................................151 

9.6.2 Centrifugal Chillers..............................................................................................................152 

9.6.3 Not-in-Kind Chiller Replacements – Absorption .................................................................152 

9.7 BANKS AND EMISSIONS RELATING TO CHILLERS............................................................................152 

9.8 REFERENCES...................................................................................................................................153 

10 VEHICLE AIR CONDITIONING .................................................................................................156

10.1 INTRODUCTION ..........................................................................................................................156 

10.1.1 Regulatory Actions affecting Vehicle Air Conditioning and Refrigerants ...........................156 

10.2 TECHNICAL PROGRESS...............................................................................................................159 

10.3 EXISTING MOBILE AIR CONDITIONING SYSTEMS.......................................................................159 

10.3.1 HFC-134a ............................................................................................................................159 

10.3.2 Retrofit of CFC-12 systems ..................................................................................................160 

10.4 OPTIONS FOR FUTURE MOBILE AIR CONDITIONING SYSTEMS....................................................160 

10.4.1 Passenger Car and Light Truck Air Conditioning ...............................................................160 

10.4.2 Bus and Rail Air Conditioning.............................................................................................164 

10.5 REFERENCES ..............................................................................................................................165 

11 REFRIGERANT CONSERVATION .............................................................................................172 

11.1 INTRODUCTION ..........................................................................................................................172 

11.2 RECOVERY, RECYCLING, AND RECLAMATION ...........................................................................173 

11.3 REFRIGERANT RECOVERY AND RECYCLING EQUIPMENT ...........................................................173 

11.4 TECHNICIAN TRAINING AND SERVICE CERTIFICATION...............................................................174 

11.5 REFRIGERANT RECLAMATION, SEPARATION, DESTRUCTION .....................................................175 

11.5.1 Reclamation and Separation ................................................................................................175 

11.6 EQUIPMENT DESIGN AND SERVICE.............................................................................................178 

11.6.1 Design ..................................................................................................................................179 

11.6.2 Charge Minimising...............................................................................................................179 

11.6.3 Installation ...........................................................................................................................179 

11.6.4 Servicing...............................................................................................................................179 

11.6.5 Reduction of Emissions through Leak Tightness..................................................................180 

11.7 DIRECT REGULATION AS A MEANS OF REFRIGERANT CONSERVATION ......................................181 

11.7.1 Financial Incentives .............................................................................................................182 

11.7.2 Required Service Practices and Leak Tightness ..................................................................183 

11.7.3 Restrictions on the sales and imports of ODSs ....................................................................184 

11.8 END-OF-LIFE ..............................................................................................................................185 

11.9 EXAMPLES OF CONSERVATION APPROACHES.............................................................................185 

11.9.1 Africa....................................................................................................................................185 

11.9.2 South America ......................................................................................................................187 

11.9.3 China....................................................................................................................................188 

11.9.4 United States ........................................................................................................................188 

11.9.5 Japan....................................................................................................................................188 

11.10 ARTICLE 5 ISSUES ......................................................................................................................189 

11.11 REFERENCES ..............................................................................................................................190 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report xi

ANNEX 1 – AUTHORS, CO-AUTHORS AND CONTRIBUTORS TO THE 2010 RTOC 

REPORT.....................................................................................................................................................192 

ANNEX 2: - EXCERPT OF THE FINAL REPORT ON GLOBAL INVENTORIES OF THE 

WORLDWIDE FLEETS OF REFRIGERATING AND AIR-CONDITIONING EQUIPMENT IN 

ORDER TO DETERMINE REFRIGERANT EMISSIONS. THE 1990 TO 2006 UPDATING............1 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report xii 

Key messages 

 The required global phase-out of HCFCs, and the need to manage the lifetime operation of 

CFC- and also HCFC-based equipment, coupled with concerns to reduce global warming, 

drive transition from ozone depleting substance (ODS) refrigerants. The technical options are 

universal, but local laws, regulations, standards, economics, competitive situations and other 

factors influence regional and local choices. 

 More than 60 new refrigerants, many of them blends, were introduced for use either in new 

equipment or as service fluids (to maintain or convert existing equipment) since the 2006 

assessment report. The primary focus for examination of new refrigerants is on unsaturated 

hydrofluorocarbons and unsaturated hydrochlorofluorocarbons. The overarching climate 

change issue as well as changing refrigerant options for refrigeration and air conditioning will 

continue to advance equipment innovations. HFCs and non-fluorochemical options are 

increasingly used in most sectors, with emphasis on optimising system efficiency (expressed 

as Coefficient of Performance - COP) and reducing emissions of high Global Warming 

Potential (GWP) refrigerants. 

 There are several low and medium GWP alternatives being considered as replacements for 

HCFC-22. These include lower GWP HFC refrigerants (HFC-32, HFC-152a, HFC-161, HFC1234yf and other unsaturated fluorochemicals, as well as blends of them), HC-290 and R-744 

(CO2). HC-290 and some of the HFC refrigerants are flammable and will need to be applied 

in accordance with an appropriate safety standard. A high degree of containment applies to all 

future refrigerant applications, either for decreasing climate impact or for safety reasons. The 

latter aspect will also increase the need to advance charge reduction technologies. 

 In commercial refrigeration stand-alone equipment, hydrocarbons (HCs) and R-744 are 

gaining market shares in Europe and in Japan; they are replacing HFC-134a, which is the 

dominant choice in most countries. In many developed countries, R-404A and R-507A have 

been the main replacements for HCFC-22 in supermarkets, however, because of their high 

GWP, a number of other options are now being introduced. Indirect systems are the most 

effective option for emissions reductions in new centralised systems for supermarkets. In two 

stage systems in Europe, R-744 is used at the low-temperature level and HFC-134a, R-744 

and HCs at the medium temperature level. 

 In industrial refrigeration, R-717 (ammonia) and HCFC-22 are still the most common 

refrigerants; R-744 is gaining in low-temperature, cascaded systems where it primarily 

replaces R-717 (ammonia), though the market volume is small. 

 In air-to-air air conditioning, HFC blends, primarily R-410A, but to a limited degree also R407C, are still the dominant near-term replacements for HCFC-22 in air-cooled systems. HC290 is also being used to replace HCFC-22 in low charge split system, window and portable 

air conditioners in some countries. Most Article 5 countries are continuing to utilise HCFC-22 

as the predominant refrigerant in air conditioning applications. 

 Up to now, car manufacturers and suppliers have evaluated several refrigerant options for new 

car (and truck) air conditioning systems including R-744, HFC-152a and HFC-1234yf, all 

with GWPs below the EU threshold of 150. These options can achieve fuel efficiency 

comparable to the existing HFC-134a systems with appropriate hardware and control 

development. The use of hydrocarbons or blends of hydrocarbons has also been considered 

but so far has not received support from vehicle manufacturers due to safety concerns. The 

eventual decision which refrigerant to select for vehicle air conditioning will be made based 

on the GWPs of the above three options along with additional considerations including 

regulatory approval, costs, system reliability, safety, heat pump capability and servicing. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 1

Abstract Executive Summary 

Current status 

The required global phase-out of HCFCs, and the need to manage the lifetime operation of CFC- and 

also HCFC-based equipment, coupled with concerns to reduce global warming, drive transition from 

ozone depleting substance (ODS) refrigerants. The technical options are universal, but local laws, 

regulations, standards, economics, competitive situations and other factors influence regional and local 

choices. The primary current solutions are summarised below. 

Refrigerants: More than 60 new refrigerants, many of them blends, were introduced for use either in 

new equipment or as service fluids (to maintain or convert existing equipment) since the 2006 

assessment report. The primary focus for examination of new refrigerants is on unsaturated 

hydrofluorocarbons and unsaturated hydrochlorofluorocarbons. Additional refrigerants are still being 

developed to enable completion of scheduled phase-outs of ODSs. Significant focus is on alternatives, 

including blend components, offering lower global warming potentials (GWPs) to address climate 

change, forcing more attention than in the past on flammable or low-flammability candidates. 

Research continues to increase and improve the physical, safety, and environmental data for 

refrigerants, to enable screening, and to optimise equipment performance. 

Domestic refrigeration: The conversion of new equipment production to the use of non-ODS 

refrigerants is essentially complete. More than one-third of newly produced units globally now use 

the refrigerant HC-600a; the balance uses HFC-134a. CFC emissions from the 150,000 tonnes 

domestic refrigerant bank are dominated by end-of-life disposal due to the high equipment reliability. 

Approximately 70% of the current, residual CFCs reside in Article 5 countries. 

Commercial refrigeration: Hydrocarbons (HCs) and R-744 (CO2) are gaining market shares for standalone equipment in Europe and in Japan; they are replacing HFC-134a, which is the dominant choice 

in most non-Article 5 and Article 5 countries. For condensing units and supermarket systems, the 

largest refrigerant bank consists of HCFC-22, which represents about 60% of the global commercial 

refrigerant bank. In developed countries, the replacement of HCFC-22 in supermarkets is dominated 

by R-404A and R-507A, however, a number of other options are used. In Europe, R-744 is used at the 

low-temperature level and HFC-134a, R-744 and HCs at the medium temperature level as alternatives 

to R-404A and R-507A because of their high GWP. 

Industrial refrigeration: R-717 and HCFC-22 are the most common refrigerants for new equipment; 

cost considerations have driven small new systems to HFC use. R-744 is gaining in low-temperature, 

cascaded systems where it primarily replaces R-717 (ammonia), though the market volume is small for 

such systems. The ODS refrigerant bank consists of 20,000 tonnes of CFCs and 125,000 tonnes of 

HCFCs and HFCs. Annual ODS emission rates are in the range of 10-25% of the total banked 

refrigerant charge. R-717 remains the primary refrigerant in large industrial systems, especially those 

for food and beverage processing and storage. 

Transport refrigeration: HCFC-22 has a low share in intermodal containers and road equipment, a 

high share in railcars (declining market) and a very high share in marine vessels. Today, virtually all 

new systems utilise HFC refrigerants (R-404A and HFC-134a). Non-fluorinated refrigerants have 

been commercialised to a small extent aboard marine vessels (R-717, R-744), and tested in marine 

containers, trailers (R-744) and trucks (HC-290). The refrigerant banks are estimated at 2,700 tonnes 

of CFCs and 27,200 tonnes of HCFC-22. The annual leak rate is in the range of 20-40%, depending on 

the specific application. 

Air-to-air conditioners and heat pumps: HFC blends, primarily R-410A, but to a limited degree also 

R-407C, are still the dominant near-term replacements for HCFC-22 in air-cooled systems. HC-290 is 

also being used to replace HCFC-22 in low charge split system, window and portable air conditioners 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 2 

in some countries. Most Article 5 countries are continuing to utilise HCFC-22 as the predominant 

refrigerant in air conditioning applications. The refrigerant bank for unitary air conditioners is in 

excess of 1 million tonnes of HCFC-22. 

Water-heating heat pumps: Air-to-water heat pumps have experienced significant growth in Japan, 

Australia, China, and Europe during the last five years, especially owing to the government incentives 

in Europe and Japan, and in the USA in prior years. HCFC-22 is currently mainly used in Article 5 

countries. The HFC blends R-410A and R407C are currently used in European and other countries. 

R-744 heat pump water heaters were introduced to the market in Japan in 2001 and have seen a steady 

growth since then, again influenced by significant subsidies. HC-290 is being applied but its use in 

Europe has decreased due to the introduction of the Pressure Equipment Directive. R-717 is mainly 

used for large capacity heat pump systems. 

Chillers: HCFC-22 has been phased out in new equipment in the developed countries, but is still used 

in Article 5 countries. Both HCFC-123 and HFC-134a are used in centrifugal chillers. HFC-134a and 

R-410A are the most common options in smaller systems with scroll and screw compressors; limited 

R-407C usage is dropping. The application of HCs and R-717 in chillers is less common and 

extremely rare as a fraction of the total in large chillers. 

Vehicle air conditioning: Today all new AC equipped passenger cars world-wide use HFC-134a; the 

transition from CFC-12 is complete for new systems, but not in old cars still in use especially in 

Article 5 countries. About one fifth of the total global refrigerant emissions are from Mobile Air 

Conditioning systems (about 60 percent if only HFC refrigerant emissions are considered); this 

includes the emissions in production, use, servicing, and end-of-life. Up to now, car manufacturers 

and suppliers have evaluated several refrigerant options for new car (and truck) air conditioning 

systems including R-744, HFC-152a and HFC-1234yf. These three options have GWPs below the EU 

threshold of 150 and can achieve fuel efficiency comparable to the existing HFC-134a systems with 

appropriate hardware and control development. The use of hydrocarbons or blends of hydrocarbons 

has also been considered but so far has not received support from vehicle manufacturers due to safety 

concerns. Most new bus or train air conditioning systems are currently equipped with the refrigerants 

HFC-134a or R-407C; fleet tests of R-744 systems in buses are ongoing. 

What is left to be achieved 

More than 100 refrigerants, including blends, are marketed at present, though approximately 20 

consitute the overwhelming majority on a global basis and even that quantity is expected to fall as 

users converge on preferred options over time. Refrigerant manufacturers are in process of developing 

new candidates while equipment manufacturers are testing, selecting, and qualifying new refrigerants 

as well as associated lubricants and other materials. The technological options for air conditioning and 

refrigeration are expected to evolve over the next several years as designers continue to replace 

HCFC-22 with non-ODS alternatives and focus on developing lower GWP alternatives for R-410A 

and R-407C. There are several low and medium GWP alternatives being considered as replacements 

for HCFC-22. These include lower GWP HFC refrigerants (HFC-32, HFC-152a, HFC-161, HFC1234yf and other unsaturated fluorochemicals, as well as blends of them), HC-290 and R-744. HC290 and some of the HFC refrigerants are flammable and will need to be applied in accordance with an 

appropriate safety standard such as IEC-60335-2-40, which establishes maximum charge levels and 

ventilation requirements. 

Several commercial chains have made good progress on the containment of refrigerant in supermarket 

systems. Indirect systems are the most effective option for emissions reductions and, in Europe, are 

gaining market share in new centralised systems for supermarkets. Technical development of 

alternatives in industrial refrigeration is expected to emphasise R-717 and R-744 in the near future. A 

significant amount of research, development and testing will be required before unsaturated HFCs can 

be deployed in large industrial systems, and even then their high refrigerant price will be an 

impediment to adoption. In heat pumps for water heating, further development of the lower GWP 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 3

options is expected. In transport refrigeration, a rapid phase-out of remaining HCFCs due to the 

relatively short life span of intermodal containers, railcars and road vehicles (10-15 years) and marine 

vessels (< 25 years) is expected. Depending on the CO2 emissions associated with the electricity 

production and the energy efficiency of the systems, there is a large potential to reduce CO2 emissions 

generated by fossil fuel operated heating systems by replacing them with heat pumps. The decision 

which refrigerant will be eventually selected for vehicle air conditioning will be made based on 

additional considerations along with the Global Warming Potential of the current alternative options 

(R-744, HFC-152a, and HFC-1234yf); these include regulatory approval, costs, system reliability, 

safety, heat pump capability and servicing. 

World-wide, a significant amount of installed refrigeration equipment still uses CFCs and HCFCs. As 

a consequence, service demand for CFCs and HCFCs will continue. Refrigerant demand for service 

needs can be minimised by preventive service, containment, recovery, and recycling. Management of 

the CFC and HCFC banks in developing countries is an important issue. A critical step to address the 

refrigerant conservation topics above is thorough training of installers and service technicians, 

together with certification and regulation. Countries where programs have been successful have had 

comprehensive regulations requiring recovery and recycling, or destruction of refrigerant. 

The way forward 

The overarching climate change issue as well as changing refrigerant options for refrigeration and air 

conditioning will continue to advance innovations in this type of equipment. Many of the lower GWP 

refrigerant options are flammable, which increases the need to advance charge reduction technologies. 

HFCs and non-fluorochemical options are increasingly used in most sectors, with emphasis on 

optimising system efficiency (COP) and reducing emissions of high-GWP refrigerants. A high degree 

of containment applies to all future refrigerant applications, either for decreasing climate impact or for 

safety reasons. The competitive market is likely to result in refrigerant options for all common 

applications and either specialty products or equipment adaptation to accommodate new refrigerants 

for all applications, but the initial indications are that reduced efficiency is likely in several key uses. 

It is worth noting that manufacturing for refrigeration, air-conditioning, and heat pump equipment for 

export is increasing and is expected to increase further in Article 5 countries. 

In domestic refrigeration, and to a lesser extent in commercial stand-alone equipment, an emerging 

trend is conversion from HFC-134a to HC-600a. Non-Article 5 countries completed the conversion 

from ODS refrigerants in domestic refrigeration approximately 15 years ago; older equipment now 

approaches the equipment useful lifetime; this results in non-Article 5 countries having a vanishing 

ODS refrigerant demand. The service demand for ODS refrigerants for domestic refrigeration in 

Article 5 countries is expected to remain strong for more than 10 years as a result of their later 

conversion to non-ODS refrigerants. In commercial stand-alone equipment in Article 5 countries, the 

use of HCs is expected to increase. For two-temperature centralised systems, R-744 is an option for 

the lower temperature level; in the near future, there will be the choice for the medium-temperature 

level for new low GWP HFCs on the one hand and R-744 or HCs on the other. In industrial 

refrigeration, there are substantial banks of CFCs in Article 5 countries and HCFCs in both nonArticle 5 and Article 5 countries that need addressing. Article 5 countries moving away from HCFCs 

(HCFC-22) might transfer to saturated HFCs, unsaturated HFCs if proven for use in industrial 

systems, to R-717 and R-744, or to other not-in-kind solutions. In transport refrigeration, HFCs will 

replace HCFCs and become a dominant refrigerant on passenger vessels and on small ships of all 

categories. The industry is working towards the use of non-fluorinated refrigerants in marine 

containers, trailers (R-744) and trucks (R-290); both are currently in the development and testing 

stage. In air-to-air air conditioning and heat pumps, HFCs, HFC blends and HC-290 are the most 

likely near-term refrigerants to replace HCFC-22 in most air conditioning applications. Contrary to 

non-Article 5 countries, the demand for service refrigerants in most Article 5 countries will consist of 

HCFC-22 and HFC-based service blends; this tendency is driven by long equipment life and is also 

due to the costs of the field conversion to alternative refrigerants. In heat pumps for water heating, 

HFC-32 or unsaturated HFCs such as HFC-1234yf or blends with this refrigerant will be studied for 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 4 

future use by taking into account the performance, costs and the necessary safety regulations in 

relation to their mild flammability. The front running candidate among global car manufacturers for 

future vehicle air conditioning systems seems to be HFC-1234yf. One manufacturer has announced 

the intention to introduce this refrigerant in car serial production in 2013. OEMs indicate that they 

will design HFC-1234yf MAC systems in such a way that these systems can safely be used with HFC134a refrigerant as well. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 5

Executive Summaries of All Chapters 

Chapter 2: Refrigerants 

More than 60 new refrigerants were introduced for use either in new equipment or as service fluids (to 

maintain or convert existing equipment) since the 2006 assessment report. Significant focus is on 

alternatives, including blend components, offering lower global warming potentials (GWPs) to address 

climate change. That pursuit forces more attention than in the past on flammable or low-flammability 

candidates. Most of the new refrigerants are blends containing hydrofluorocarbons (HFCs) or in some 

cases blends of HFCs and hydrocarbons (HCs), the latter typically added to achieve miscibility with 

compressor lubricants to facilitate lubricant return to compressors. 

Additional refrigerants including blend components still are being developed to enable completion of 

scheduled phase-outs of ozone-depleting substances (ODSs). They include unsaturated 

fluorochemicals with primary focus on unsaturated HFCs and hydrochlorofluorocarbons (HCFCs), 

also identified as hydrofluoro-olefin (HFO) and hydrochlorofluoro-olefin (HCFO) compounds. 

Considerable effort continues for examination of broader use of ammonia, carbon dioxide, and HCs. 

Research continues to increase and improve the physical, safety, and environmental data for 

refrigerants, to enable screening, and to optimise equipment performance. 

The report updates and expands summary data for assessment of the new refrigerants as well as 

comparison to refrigerants already retired or being replaced as ODSs or for other environmental, 

performance, or safety reasons. The environmental data included are consistent with the 2010 WMO 

Scientific Assessment supplemented with additional data, to fill voids, from other consensus 

assessments and published studies. 

The new assessment updates the tabular data summaries from prior assessments. The revised data 

reflect consensus assessments and published scientific and engineering literature where possible. The 

summaries address refrigerant designations, chemical formulae, normal boiling point (NBP), critical 

temperature (Tc), occupational exposure limits, lower flammability limit (LFL), safety classification, 

atmospheric lifetime (tatm), ozone depletion potential (ODP), global warming potential (GWP), and 

control status. The updated chapter also summarises the ODP and GWP values prescribed for 

regulatory reporting. 

The status of data for the thermophysical properties of refrigerants, which include both 

thermodynamic properties (such as density, pressure, enthalpy, entropy, and heat capacity) and 

transport properties (such as viscosity and thermal conductivity), is generally good for the most 

common and alternative refrigerants. Data gaps exist, however, for the thermodynamic and transport 

properties of blends and less-common fluids as well as for the transport properties of many fluids (but 

especially so for blends and for some of the new unsaturated fluorochemicals and blends containing 

them). The data situation for the less-common fluids is more variable; there is a need to collect and 

evaluate the data for such candidates. Significant research still is needed, but is not expected to retard 

scheduled ODS phase-outs. 

A major uncertainty for all of the refrigerants is the influence of lubricants on properties. The working 

fluid in most systems is actually a mixture of the refrigerant and the lubricant carried over from the 

compressor(s). Research on refrigerant-lubricant mixtures is continuing. The need for further studies 

is driven by the introduction of new refrigerants, by the great variety of lubricants in use and being 

introduced, and by the often highly proprietary nature of the chemical structures of the lubricant 

and/or additives. 

This chapter summarises data for refrigerants and specifically those addressed in subsequent sections 

of this assessment report. It discusses thermophysical (both thermodynamic and transport) properties 

as well as heat transfer, compatibility, and safety data. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 6 

This chapter does not address the suitability, advantages, and drawbacks of individual refrigerants or 

refrigerant groups for specific applications; such discussion is addressed for specific applications 

where relevant in subsequent chapters. 

The updated chapter reviews the status heat transfer and compatibility data for refrigerants. It 

recommends further research of: 

 test data for shell-side boiling and condensation of zeotropic mixtures 

 local heat transfer data determined at specific values of vapour quality 

 microchannel heat exchanger refrigerant-side heat transfer data including flow distribution 

effects 

 effects of lubricants on heat transfer, especially for ammonia, carbon dioxide, 

hydrocarbons, unsaturated HCFCs, and unsaturated HFCs 

 more accurate evaporation and condensation data for hydrocarbons for both plain tube and 

enhanced tubes 

 inside-tube condensation heat transfer data for carbon dioxide at low temperatures such as 

–20 °C 

 heat transfer correlations for carbon dioxide supercritical heat rejection and two-phase 

evaporation 

Chapter 3: Domestic Refrigeration 

Conversion of new domestic refrigerator production to non-ODS refrigerants is essentially complete. 

Broad-based refrigerant alternatives continue to be HC-600a and HFC-134a. In 2008, 36% of 

production units used HC-600a or a binary blend of HC-600a and HC-290; 63% used HFC-134a. The 

remaining 1% used regionally available refrigerants, such as HFC-152a. Second generation non-ODS 

refrigerant conversion from HFC-134a to HC-600a is complete in Japan and has begun in the United 

States and other countries. Significant extension of this second generation conversion is expected over 

the next decade. By 2020 it is estimated that three-fourths of refrigerant demand for new refrigerator 

production will be for HC-600a and one-fourth will be for HC-134a. No new technologies have 

surfaced which are cost and efficiency competitive with current vapour-compression technology. 

Service conversion to non-ODS refrigerants has significantly lagged original equipment conversion. 

The distributed, individual-proprietor character of the service industry resists co-ordinated refrigerant 

management efforts. Field service procedures typically use originally specified refrigerants. NonArticle 5 countries completed new production conversion from ODS refrigerants approximately 15 

years ago. This time span is approaching the useful equipment lifetime so service of ODS refrigerant 

containing products is transitioning to a sunset issue in these countries. Service demand for ODS 

refrigerants in Article 5 countries is expected to remain strong for more than ten years as a result of 

their later conversion to non-ODS refrigerants. Unless there is governmental intervention, service 

demand for CFC-12 refrigerant is expected to continue. 

Enhanced product energy efficiency provides benefit to reduced global warming during the use phase 

of the refrigerator life cycle. Existing state-of-the-art models contain multiple, mature efficiency 

improvement options. Extension of these to all global products would yield significant benefits, but 

realisation will be constrained by capital funds availability. 

In 2006 the global domestic refrigerant bank was estimated to be 153,000 tonnes consisting of 40% 

CFC-12, 54% HFC-134a and 6% HC-600a. The bank is equally divided between non-Article 5 and 

Article 5 countries. An estimated 71% of residual CFCs reside in Article 5 countries. Annual 

emissions from this bank were estimated to be 6.8%. The majority of domestic refrigerators never 

require sealed system service. Consequently, emissions are dominated by end-of-life product 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 7

disposition; inferring legacy product emission management may be the largest opportunity for 

emission avoidance. 

Chapter 4: Commercial Refrigeration 

Commercial refrigeration comprises three different families of systems: centralised systems installed 

in supermarkets, condensing units installed mainly in small shops and stand-alone units installed in all 

types of shops. The refrigerant choices depend on the levels of conservation temperatures and the type 

of systems. 

The number of supermarkets world-wide is estimated to 280,000 in 2006 covering a wide span of sales 

areas varying from 400 m2 to 20,000 m2. The populations, in 2006, of vending machines and other 

stand-alone equipment are evaluated to 20.5 and 32 million units, respectively, and condensing units 

are estimated to 34 million units. In 2006, the refrigerant bank was estimated at 340,000 tonnes and 

was distributed as follows: 46% in centralised systems, 47% in condensing units, and 7% in standalone equipment. The estimated sharing of refrigerant per type is about 15% CFCs which are still in 

use in Article 5 countries, 62% HCFCs the dominant refrigerant bank and still for many years, and 

23% HFCs which have been introduced in new equipment in Europe and Japan as of 2000. 

Stand-alone Equipment: HFC-134a fulfils most technical constraints in terms of reliability and 

energy performance for stand-alone equipment. When GWP of HFC-134a is considered prohibitive in 

relation to HFC emissions (country regulation or company policy), hydrocarbon refrigerants 

(isobutane and propane, i.e. HC-600a and HC-290) or CO2 (R-744) are the current alternative 

solutions, presenting in most of the cases the same technical reliability and energy performance as 

HFC-134a. In the near future, unsaturated HFCs such as HFC-1234yf could be considered as an 

adapted solution, since the retrofit from HFC-134a to this new refrigerant is expected being rather 

simple, even if long term reliability has to be assessed. Energy efficiency standards are being issued or 

revisited in order to lower energy consumption of various types of stand-alone equipment. 

Condensing Units: Their cooling capacities vary from 5 to 20 kW mostly at medium temperature. The 

refrigerant charge varies from 1 to 5 kg for HCFCs or HFCs and also HCs. HCFC-22 is still the most 

used refrigerant in the U.S. and in all Article 5 countries. For new systems, R-404A is the leading 

choice for cost reasons; the condensing units using the refrigerant R-404A are cheaper compared to 

HFC-134a units of the same cooling capacity because of smaller compressor. Nevertheless in hot 

climate and for medium temperature applications, HFC-134a is used due to its better energy 

performances at high ambient temperatures. 

Supermarket systems: The size of centralised systems can vary from refrigerating capacities of about 

20 kW to more than 1 MW related to the size of the supermarket. Refrigerant charges range from 40 

up to 1500 kg per installation. The dominant refrigerant used in centralised systems is still HCFC-22. 

In Europe, new systems have been mainly charged with R-404A, but HFC-134a, ammonia (R-717), 

HCs and R-744 have been tested in many stores. R-744 is now considered off the shelf solution by the 

two major European manufacturers. Several designs have been experimented in hundreds of stores: 

distributed systems, indirect systems, cascade systems. Those designs have been developed in order to 

reduce the refrigerant charge to use more easily flammable or toxic refrigerants, or to limit the charge 

of high GWP HFCs. At the low temperature level the use of R-744 appears as an interesting option in 

terms of GWP, energy efficiency and even costs especially when HFCs are highly taxed. At the 

medium level temperature, the search for the best option is still ongoing. In the near term, servicing of 

current HCFC-22 may pose a problem due to possible shortage of this refrigerant. Several HFC blends 

are proposed to retrofit HCFC-22 installations with or without oil change, but those retrofit blends 

have not gained until now a significant momentum. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 8 

Chapter 5: Industrial Systems 

Industrial systems are characterised primarily by the size of the equipment and the temperature range 

covered by the sector. This includes industrial cooling, industrial heat pumps and industrial airconditioning. Industrial systems have special design requirements, including the need for 

uninterrupted service, which are not typically provided by traditional HVAC practices. Rankine cycle 

electrical generation systems using relevant fluids are also considered in the industrial systems 

chapter. 

R-717 is the most common refrigerant in industrial systems, although with significant regional 

variations around the world. Where R-717 is not acceptable for toxicity reasons, R-744 has been used, 

either in cascade with a smaller R-717 plant, in cascade with a fluorocarbon or rejecting heat direct to 

atmosphere in a high pressure (“transcritical”) system. In some cases, for example freezers or IT 

equipment cooling, R-744 offers additional advantages in performance or efficiency which merit 

selection ahead of any other refrigerant without consideration of toxicity or environment. 

There is also a significant bank of HCFC refrigerant in industrial systems, particularly HCFC-22. 

Individual system charge can be high – in some cases several tonnes of refrigerant. These systems 

tend to have longer life than commercial equipment, often lasting over 20 years, but leakage rates can 

be high, particularly in older plants. A “drop-in” blend for replacing HCFC-22 in flooded industrial 

systems has not been developed; the common replacement blends used in commercial refrigeration 

such as R-407A or R-422D are difficult or impossible to use in large industrial systems. The cost of 

these blends is also a significant barrier to their use. 

HFCs have not been widely used in large industrial systems. Where they have been adopted it is 

generally in low charge systems in order to reduce the financial consequences of refrigerant loss. It is 

very unlikely that unsaturated HFC refrigerants, whether single compounds or blends, will be adopted 

for use in industrial systems because in addition to cost considerations the risk of refrigerant 

decomposition due to the presence of contaminants is too great. HFC-245fa and HFC-134a have also 

been used in power generation units, utilising the Rankine cycle, although these systems are not yet 

widely available on the market. 

Users of HCFCs in smaller industrial systems are now faced with the choice of whether to switch to 

HFCs and face a possible phase-down, or to change to R-717 or R-744 and deal with the change in 

operating practices that those refrigerants would require. 

Chapter 6: Transport Refrigeration 

Transport refrigeration includes transport of chilled or frozen products by means of road vehicles, 

railcars, intermodal containers, and small insulated containers (less than 2 m3

) and boxes. It also 

includes use of refrigeration and air conditioning on merchant, naval and fishing vessels above 100 

gross tonnes (GT) (about over 24 m in length). 

Transport refrigeration is a niche market in terms of refrigerant banks compared to other sectors. There 

are about 4,000,000 road transport refrigeration units, and about 950,000 marine container units in 

operation today, to mention the largest segments in terms of fleet size. Most equipment has a 

refrigerant charge below 6 kg. Although refrigerant charge can reach several tons aboard large vessels, 

their fleet is relatively small. There are approx. 150,000 marine vessels above 100 GT in the world 

fleet; thereof small and medium size vessels have the largest share. 

The equipment lifetime is usually between 10 and 15 years for intermodal containers, railcars and road 

vehicles, and 20 to 25 years for equipment aboard marine vessels. 

The vapour compression cycle is the technology used predominantly in transport refrigeration 

equipment. CFC and HCFC refrigerants can be found in older equipment. HCFC-22 has a low share in 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 9

intermodal containers and road equipment, but a high share in railcars (declining market) and a very 

high share in marine vessels, where it remains to be the dominant refrigerant. The CFC and HCFC 

banks have been decreasing. Retrofit options to R-502 include R-408A, R-402A and R-404A. 

Virtually all new systems utilise HFC refrigerants (HFC-134a, R-404A). Non-fluorinated refrigerants 

have been commercialised to a small extent aboard marine vessels (R-717, R-744), and tested in 

marine containers, trailers (R-744) and trucks (R-290). A wider application of these refrigerants in 

practice has not been possible so far because of various technical constraints. There is no practical 

experience with HFC-1234yf and other low-GWP candidate fluids in transport refrigeration. 

Although hydrocarbons are technically feasible and may even outperform HFC systems, flammability 

makes people concerned about their use. Where they do not exist, standards need to be developed to 

address the safety concerns. 

Carbon dioxide (R-744) is one of a few promising solutions in transport refrigeration. While direct 

emissions of R-744 are negligible, indirect emissions of R-744 may be comparable to HFCs depending 

on the climate where the vehicle is operated. Aboard marine vessels, because operation under high 

ambient temperatures is commonly required, R-774 use has been limited to low temperature stages of 

cascade or indirect system applications. 

Due to safety concerns, use of ammonia (R-717) has been limited to indirect and cascade systems on 

larger ships which do not carry passengers but professional crew only. HFC refrigerants will continue 

to be used on passenger vessels, and on small ships of all categories. Ammonia has not been used in 

road vehicle and container transport in vapour compression cycles. 

The transport industry is working to reduce the overall CO2 emissions. The refrigerant type can 

influence both direct and indirect equivalent CO2 emission of a vehicle. Refrigerant charge reduction, 

refrigerant leakage rate minimisation (for example use of hermetic/semi-hermetic compressors instead 

of open drive), and the use of low-GWP refrigerants influence the direct contribution. Design changes 

that would improve the energy efficiency can reduce the indirect contribution. 

Transition of power supply systems from traditional diesel engines to alternative propulsion systems 

(hybrid, electric, etc.) will influence refrigerantion system change and the choice of low-GWP 

refrigerants in the future. 

As in other refrigeration sectors, research and development of other not-in-kind systems, such as 

magnetic or acoustic refrigeration, remains in the laboratory prototype stage. Absorption and 

adsorption systems with water are under development too. 

Chapter 7: Air-to-air air conditioners and heat pumps 

On a global basis, air conditioners for cooling and heating (including air-to-air heat pumps) ranging in 

size from 2.0 kW to 420 kW comprise a significant segment of the air conditioning market (the 

majority are less than 35kW). Nearly all air conditioners and heat pumps manufactured prior to 2000 

used HCFC-22 as their working fluid. The installed base of units in 2008 represented an estimated 

HCFC-22 bank exceeding one million metric-tonnes. Approximately 85% of the installed population 

uses HCFC-22. In 2008, HFC demand globally represented approximately 32% of the total refrigerant 

demand for these categories of products. Most Article 5 countries are continuing to utilise HCFC-22 

as the predominant refrigerant in air conditioning applications. 

Options for new Equipment 

HFC refrigerant blends R-410A and R-407C are the dominant alternatives being used to replace 

HCFC-22 in air-conditioners. HC-290 is also being used to replace HCFC-22 in products having low 

refrigerant charges. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 10 

Air conditioners using R-410A and R-407C are widely available in most non-Article 5 countries. Also, 

equipment using R-410A and R-407C is being manufactured in some Article 5 countries; especially in 

China where a large export market has created demand for these products. However, these units are 

typically not sold in the domestic market because of their higher cost. 

There are several low and medium GWP alternatives being considered as replacements for HCFC-22 

and the high GWP HFCs (R-410A and R-407C). These refrigerants include lower GWP HFC 

refrigerants, HC-290 and R-744. HC-290 and some of the HFC refrigerants are flammable and will 

need to be applied in accordance with an appropriate safety standard such as IEC-60335-2-40, which 

establishes maximum charge levels and ventilation requirements. 

A number of moderate and low GWP HFC refrigerants are being considered for use in air 

conditioners. These include HFC-32, HFC-152a, HFC-161, HFC-1234yf and blends of HFC-1234yf 

with other refrigerants: 

 HFC-32 is a class A2L flammable HFC having a GWP of 675, which is approximately 30% 

that of R-410A. R-410A systems can be redesigned for HFC-32 with minor modifications. 

However, because of its A2L flammability rating it will need to be applied using a safety 

standard such as IEC-60335-2-40. 

 HFC-152a is an A3 flammable low GWP HFC having thermodynamic characteristics similar 

to HFC-134a. While it has been evaluated as an alternative to HCFC-22, it is unlikely to be 

commercialised in unitary air conditioning applications because its low density and 

flammability result in significantly increased system costs. 

 HFC-161 is a flammable low GWP refrigerant, which is being evaluated as a low GWP 

alternative to HCFC-22. Like all flammable refrigerants, it would need to be applied using 

appropriate safety standards. 

 Pure HFC-1234yf is not likely to be used as a replacement for HCFC-22 in air conditioners 

because of its low volumetric capacity. However, HFC-1234yf can be blended with other 

non-ODP refrigerants to arrive at thermodynamic properties similar to either HCFC-22 or R410A. Blends of this type are under development, but are not commercially available. 

Hydrocarbon refrigerants are also low GWP alternatives to HCFCs and HFCs for low charge 

applications. The most frequently used hydrocarbon refrigerant in air conditioning applications is HC290. The high flammability of HC-290 limits its use to lower charge applications. All flammable 

refrigerants need to be applied using an applicable safety standard such as IEC-60335-2-40, which 

addresses the design requirements and charge limits for flammable refrigerants. Several manufacturers 

in China and India are now introducing low charge HC-290 split air conditioners. 

R-744, CO2, offers a number of desirable properties as a refrigerant. However, R-744 has a low 

critical point temperature, which results in significant efficiency losses when it is applied at the typical 

indoor and outdoor air temperatures of air-to-air air conditioning applications; particularly in high 

ambient climates. However, a number of cycle enhancements and component additions can be made 

to improve the efficiency of R-744 systems. While the addition of efficiency enhancing components 

can improve the efficiency of R-744 systems, they also substantially increase the system cost. In order 

for R-744 systems to become commercially viable, cost effective mitigation of the efficiency issue will 

be required. 

High Ambient Considerations 

In the near term, regions with hot climates should be able to rely on the refrigerants and technologies 

that are currently commercially available to replace HCFC-22 (R-407C, R-410A and HC-290). 

However, when replacing HCFC-22 products with those using R-410A or R-407C the application 

engineer may need to take special consideration of the reduced capacity at the design ambient 

temperature when sizing the equipment for the design cooling load. When replacing HCFC-22 in low 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 11

charge applications (small split, window and portable room air conditioners), the system designer may 

want to consider the use of HC-290. In the longer-term products using HFC-32, new low and medium 

GWP HFC blends and HC-290 are the preferable options for high ambient air conditioning 

applications. R-744 is not a preferred option for high ambient air conditioning applications because its 

very low critical temperature results in significant performance degradation during high ambient 

operation. 

Chapter 8: Water heating heat pumps 

Heat pumps are classified by heat source (air, water, or ground) and heat sink (air, water), resulting in 

designations such as “air to water” (air source, water sink) heat pumps. This chapter covers only 

systems where water is the sink. The products for industrial process heating are covered in chapter 5 

“Industrial systems”. Air-to-air heat pumps are covered in chapter 7 (Air-to-air air conditioners and 

heat pumps). 

Heat pump water heaters are designed especially for heating service hot water (including domestic 

water) to a temperature between 55 and 90 oC. 

Space heating heat pumps heat water for distribution to air handling units, radiators, or under-floor 

panels. The required water temperature depends on the type of emitter, low temperature application 

ranging from 25 to 35°C for under floor heating, for moderate temperature application such as air 

handling units around 45 °C, for high temperature application such as radiant heating 55 to 60°C and 

for very high temperature application as high as 65 to 80°C such as for the fossil fuel boiler 

replacement market. The required warm water temperature affects the selection of the refrigerant. Heat 

pump systems are more efficient at lower sink temperatures, but each product must fulfil the required 

operating temperature.

Air-to-water heat pumps have experienced significant growth in Japan, Europe, China, and Australia 

during the last five years. 

Efficient heat pumps can reduce global warming impact compared with fossil fuel burning systems 

significantly. The reduction depends on the efficiency level of the heat pump and the carbon emission 

per kWh of the electricity generation. The tendency of decarbonisation of electricity strengthens this 

positive effect year by year. Also the efficiency levels of the heat pumps are improving year by year. 

However, heat pumps tend to be higher in cost than fossil fuel systems because they employ 

complicated refrigerant circuits, larger heat exchangers and other special features. Government support 

programmes in Europe and Japan to promote heat pump systems have resulted in a rapid growth of 

heat pump system sales in recent years. More than 1 million air-to-water heat pumps were sold worldwide in 2008. Predictions of sales show very large growths in USA, Japan, China and Europe. 

Current refrigerant options for new heat pumps 

HFC-134a and HFC blends R-407C and R-410A are currently used for new water heating and space 

heating heat pumps to replace HCFC-22, R-407C with limited product redesign and R-410A for 

completely redesigned products. 

HC-290 has properties similar to those of HCFC-22 apart from flammability. Until 2004 almost half of 

the heat pumps sold in the EU used HC-290. Use in Europe has declined due to introduction of 

Pressure Equipment Directive. 

Development of R-744 heat pumps started around 1990. R-744 heat pump water heaters were 

introduced to the market in Japan in 2001, with heat pumps for heating of bath or sanitary water as the 

main application. The market for heat pump water heaters in Japan is steadily growing based on 

government and utility incentives. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 12 

Although the current market for space heating heat pumps for commercial buildings with combined 

radiator and air heating systems is limited, R-744 is considered to be a promising refrigerant. 

R-717 is a non-ODS refrigerant and has a very low GWP, but it has higher toxicity and lower 

flammability characteristics. R-717 is used mainly for large capacity systems. 

Future Refrigerant Options for New heat pumps 

HFC-32 has a lower GWP of one third of R-410A. Heat pumps with HFC-32 can achieve lower 

charge than heat pumps with R-410A. HFC-32 has a low flammability with a low burning velocity. 

HFC-1234yf is similar in thermophysical properties to HFC-134a. For water heating and space heating 

heat pumps using HCFC-22, R-410A, R-407C, significant design changes would be required to 

optimise for HFC-1234yf. HFC-1234yf has low flammability with a low burning velocity. Due to the 

GWP value it has high potential in applications in systems that currently use HFC-134a. As sample 

supply of these refrigerants is very limited, it is too early to judge whether any of these chemicals will 

be commercialised and will show acceptable performance in heat pump systems. 

Future refrigerants options for new heat pumps include current options R-410A, HFC-134a, HC-290, 

HC 600a, R-744, and R-717 as well as HFC-32 and new refrigerants. 

Since the numbers of heat pumps covered by this chapter still are limited, the refrigerant bank is 

relatively small. Accordingly, the refrigerant emissions are low compared to other products. On the 

other hand, heat pumps will increase in quantity leading to higher net refrigerant requirements and 

emissions in the future. However, it is important to emphasise that there is a large potential to reduce 

CO2 emission generated by fossil fuel combustion systems by replacing them with heat pump systems. 

Chapter 9: Chillers 

Chillers predominantly are used for comfort air conditioning in commercial buildings and building 

complexes. They are coupled with chilled water distribution and air handling/air distribution systems. 

Chillers also are used for cooling in commercial and industrial facilities such as data processing and 

communications centers, electronics fabrication, and molding. 

Air-cooled chillers in capacities up to 1800 kW represent approximately 80 % of the annual unit 

production in chillers using positive displacement compressors (reciprocating piston, scroll, and 

screw). HFC-134a and R-410A are the most common refrigerants with the phase-out of HCFC-22. R407C has been used as a transition refrigerant. Some chillers are available with R-717 or hydrocarbon 

refrigerants – primarily HC-290, HC-600a, or HC-1270. Such chillers are manufactured in small 

quantities compared to HFC-134a and R-410A chillers of similar capacities and require attention to 

flammability, and for R-717 also toxicity concerns, as reflected in safety codes and regulations. 

Chillers employing R-744 as the refrigerant are being marketed. 

For water-cooled chillers, both positive displacement compressors and centrifugal compressors are 

used. Positive displacement water-cooled chillers employ the same refrigerants as the air-cooled 

versions. Centrifugal chillers are dominant above 2 MW. Centrifugal chillers are provided with 

HCFC-123 or HFC-134a refrigerants though extremely limited use is made of HFC-245fa. HCFC-123 

offers an efficient, very-low GWP option for centrifugal chillers. Under terms of the Montreal 

Protocol, use of HCFC-123 in new equipment will end in most developed countries by 2020 and by 

2030 in Article 5 countries. 

Existing chillers employing CFC refrigerants are being replaced slowly by new chillers using HCFC123 or HFC-134a. Today’s new chillers use 25-50% less electricity than the CFC chillers produced 

decades ago, so the savings in energy costs often justify replacement of ageing CFC chillers. R-717 is 

not suitable for use in centrifugal chillers as its use would require four or more stages or, in very large 

capacities, a switch to axial compressor designs. 

A continuing trend in chiller development is to improve both full-load and seasonal energy efficiency 

to address both energy-related global warming impacts and operating costs. A number of methods are 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 13

used to achieve higher seasonal efficiencies. These include multistage compression with interstage 

economisers, use of multiple compressors to accommodate part-load conditions, continuous unloading 

capabilities for screw compressors, enhanced electronic controls, variable-speed compressor drives, 

and optimal sequencing of multiple chillers to maximise overall efficiency. 

Refrigerants suggested as alternatives to ODS or high-GWP refrigerants in chillers include R-717, 

hydrocarbons, R-744, R-718, HFC-32, and new low-GWP refrigerants such as HFC-1234yf. Chillers 

using R-718 as refrigerant carry a cost premium over conventional systems because of their larger 

physical size and the complexity of their compressor technology, often entailing axial compressor 

designs operating under high vacuum. HFC-1234yf and other low- or ultra-low GWP refrigerants are 

too new to allow assessment of their suitability for use in chillers at this time, though that is likely to 

change in subsequent assessments. 

Absorption chillers using working pairs ammonia-water (primarily in small capacities) or waterlithium bromide (generally in large capacities) are an alternative to chillers employing the vapourcompression cycle. They are particularly suitable for applications where surplus heat can be recovered. 

Other not-in-kind technologies in the research stage, such as thermoacoustic or magnetocaloric 

technologies, still are not ready for commercialisation and may not be found suitable or competitive. 

Of particular note for both ozone depletion and global climate change, chillers as a group incur very 

low release rates for refrigerants. The environmental impact of chillers is dominated by the energyrelated global warming associated with their energy consumption over their operating life (typically 20 

years and sometimes longer than 40 years). Refrigerant emissions, with their direct global warming 

contributions, are a small fraction of the total global warming impact of chillers except for regions 

with very low carbon intensity for power generation. 

Chapter 10: Vehicle air conditioning 

Today all new passenger cars world-wide sold with air conditioning systems are using HFC-134a and 

the transition from CFC-12 is complete. About one fifth of the total global refrigerant emissions are 

from MACs (about 60 percent if only HFC refrigerant emissions are considered) including the 

emissions in production, use, servicing, and end-of-life. In the USA, 19% of the fleet of passenger 

vehicles is still using CFC-12 refrigerant based on recent survey results. The European Union has in 

place legislation for cars and light trucks banning the use of refrigerants with GWP>150 [e.g.; HFC134a] in new-type vehicles from 2011 and all new vehicles from 2017. There are limited replacement 

refrigerants with a global warming potential (GWP) less than 150. Other countries will probably 

follow the regulatory direction of the EU or provide incentives to reduce the usage of HFC-134a in 

vehicles. 

For MAC systems, the use of hydrocarbons or blends of hydrocarbons as a refrigerant has been 

investigated but has so far not received support from vehicle manufacturers as a possible alternative 

technology due to safety concerns. In Australia and the North America, hydrocarbon refrigerants have 

been introduced as drop-in refrigerants to replace CFC-12 (which is illegal in the USA and in some 

Australian states). These same refrigerants are used to a lesser extent for a replacement of HFC-134a. 

Up to now, car manufacturers and suppliers have evaluated three refrigerant options for new car and 

truck air conditioning systems, R-744, HFC-152a and HFC-1234yf. All three have GWPs below the 

EU threshold of 150 and can achieve fuel efficiency comparable to existing HFC-134a systems. The 

CO2 equivalent impact of direct emissions from the refrigerant over the vehicle lifetime is much less 

than the impact related to the energy required to operate the system. The energy required to operate 

the MACs results in increased CO2 vehicle tail pipe emissions. Therefore, MAC systems designed to 

provide efficient cooling performance have become the major environmental goal. With the usage of 

appropriate controls and components, all three refrigerant options have been demonstrated to be 

comparable to HFC-134a with respect to cooling performance and total CO2 equivalents of MAC 

systems. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 14 

Hence, the global warming impact is almost identical for all three refrigerant options when considered 

on a global basis. Adoption of any of the refrigerant choices would therefore be of similar 

environmental benefit. The decision of which refrigerant to choose will have to be made based on 

other considerations, such as regulatory approval, cost, system reliability, safety, heat pump capability, 

suitability for hybrid electric vehicles, and servicing. 

The emerging global car manufacturers’ refrigerant choice for future car air conditioning systems 

seems to be HFC-1234yf and one manufacturer has announced the intention to introduce this 

refrigerant in car serial production in 2013. Currently, hurdles exist (miscibility with oil, stability 

problems in the presence of small amounts of water and air in the air conditioning system, mixing with 

HFC-134a, additional costs) that will require resolution prior to the commercial implementation of 

HFC-1234yf as refrigerant for car air conditioning. OEM’s indicate that they will design HFC-1234yf 

MAC systems in such a way that these systems can safely be used with the refrigerant HFC-134a as 

well. This will affect the world-wide transition from HFC-134a to HFC-1234yf for MAC systems. 

The development status of other refrigeration technologies, like sorption or thermoelectric systems, are 

still far away from serial production and presently show very poor price competitiveness and poor 

system performance and efficiency. 

The rapid evolution of hybrid electric vehicles and electric vehicles with electrically driven 

compressors introduces new challenges for any new alternative refrigerant. 

At present, no regulation exists that controls the use of fluorinated greenhouse gases as refrigerants for 

MAC systems in buses and trains. It is likely that the choice of refrigerant of passenger car air 

conditioning systems will influence the choice of refrigerant for air conditioning systems in buses and 

trains. 

World-wide, an approximate 50% of the bus and train fleet is still equipped with HCFC-22 systems. 

The rest use mostly HFC-134a or R-407C systems. Most new bus or train air conditioning systems are 

equipped with the refrigerants HFC-134a or R-407C. The only reported low GWP refrigerant activities 

are on-going fleet tests of R-744 systems in buses. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 15

Chapter 1 

__________________________________________________________ 

Introduction 

Chapter Lead Authors 

Lambert Kuijpers 

Roberto de A. Peixoto 
16 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

1 Introduction 

1.1 Montreal Protocol Developments 

In 1981, the United Nations Environment Programme (UNEP) began negotiations to develop 

multilateral protection of the stratospheric ozone layer. These negotiations resulted in the Vienna 

Convention for the Protection of the Ozone Layer, adopted in March 1985. In September 1987, 24 

nations, amongst which the United States, Japan, the Soviet Union, a large number of Western 

European countries, Egypt, Ghana, Kenya, Mexico, Panama, Senegal, Togo and Venezuela, as well as 

the European Community as a regional organisation, signed the Montreal Protocol on Substances that 

Deplete the Ozone Layer. The Montreal Protocol entered into force on January 1, 1989. This 

international environmental agreement originally limited production of specified CFCs to 50 percent 

of the 1986 levels by the year 1998 and called for a freeze in production of specified halons at 1986 

levels starting in 1992. By April 1991, 68 nations had already ratified the Protocol: these represented 

over 90 percent of the 1991 world production of CFCs and halons. At present all countries in the 

world have ratified the Vienna Convention and the Montreal Protocol, so its Decisions are truly 

global. 

Shortly after the 1987 Protocol was negotiated, new scientific evidence conclusively linked CFCs to 

the depletion of the ozone layer and indicated that depletion had already occurred. Consequently, 

many countries called for further actions to protect the ozone layer by expanding and strengthening the 

original control provisions of the Montreal Protocol, and they decided that an assessment should be 

carried out in the year 1989. 

In June 1990, the Parties to the Montreal Protocol met in London, considered the data from the 1989 

Assessment Reports, and agreed to Protocol adjustments requiring more stringent controls on the 

CFCs and halons as specified in the original agreement. They also agreed to amendments placing 

controls on other ozone depleting substances, including carbon tetrachloride and 1,1,1-trichloroethane. 

In London, a new assessment was again decided, which was carried out in 1991 for consideration in 

1992. The London Amendment acknowledged the need for financial and technical assistance of the 

developing countries, and established a (Interim) Multilateral Fund. 

At their 4th Meeting in Copenhagen, Denmark, the Parties considered the Assessment Reports and 

took decisions that again advanced the phase-out schedules in non-Article 5 countries for most ozone 

depleting substances, including methyl bromide. They continued the financial mechanism and decided 

a new assessment to be carried out in 1994 (Decision IV/13), for decisions by the Parties at their 1995 

Meeting. 

At the 7th Meeting in Vienna (November 1995) the Parties considered the Assessment Reports and 

focused on the progress made in phasing out ozone depleting chemicals. A reduction in the maximum 

permissible annual consumption of HCFCs (the “cap”) for the developed countries was decided (2.8% 

instead of 3.1%, as decided in Copenhagen). A control schedule for the HCFC consumption for the 

Article 5 countries was agreed upon (in fact, this consisted of a freeze in consumption by the year 

2016 and a phase-out by the year 2040). Article 5 countries also agreed to freeze their methyl bromide 

consumption by the year 2005. The Parties, in Decision VII/34, requested a new assessment to be 

carried out by the Assessment Panels in the year 1998. 

Updated and more detailed Terms of Reference for the Technology and Economic Assessment Panel 

and its Technical Options Committees (compared to the original 1989 ones) were decided and were 

given in the 1996 Report of the Technology and Economic Assessment Panel (these TOR were again 

considered in the light of disclosure of interest and conflict of interest at the 18th Meeting of the 

Parties (2006) in New Delhi, where a separate Decision on these topics was taken). 

The 15th Meeting of the Parties, held in Nairobi in November 2003, considered the 2002 Assessment 

Reports, next to a number of other issues, including destruction technologies, process agent uses and 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 17

the handling and destruction of foams at end-of-life. Parties decided to request the Assessment Panels 

to update their 2002 reports in 2006 and submit them to the Secretariat by 31 December 2006 for 

consideration by the Open-ended Working Group and by the Nineteenth Meeting of the Parties in 

2007 (MOP-19, to be held in Montreal, September 2007). In the relevant Decision (XV/53), the 

Parties also requested the TEAP to consider, among other matters, five specific issues, including "(c) 

Technically and economically feasible choices for the elimination of ozone-depleting substances by 

the use of alternatives that have superior environmental performance with regard to climate change, 

human health and sustainability;" and "(e) Accounting of the production and use of ozone-depleting 

substances and of ozone-depleting substances in inventory or contained in products". 

The 19th Meeting of the Parties, held in Montreal in September 2007 (on the occasion of the twentieth 

Anniversary of the Protocol) reached agreement to adjust the Montreal Protocol's HCFC phase-out 

schedule to accelerate the phase-out of production and consumption of HCFCs. This decision will 

result in significant reduction of ozone depletion and well as of global warming or global climate 

forcing. This meeting also considered all 2006 Assessment Reports, next to a large number of other 

issues. Parties decided to request the Assessment Panels to update their 2006 reports in 2010 and 

submit them to the Secretariat by 31 December 2010 for consideration by the Open-ended Working 

Group and by the Twenty-Third Meeting of the Parties in 2011 (MOP-23). In the relevant Decision 

(XIX/20), the Parties also requested the TEAP (and its TOCs) in paragraph 6 to consider 

(a) The impact of the phase-out of ozone-depleting substances on sustainable development, 

particularly in Parties operating under paragraph 1 of Article 5 and countries with economies 

in transition; 

(b) Technical progress in all sectors; 

(c) Technically and economically feasible choices for the reduction and elimination of ozonedepleting substances through the use of alternatives, taking into account their impact on 

climate change and overall environmental performance; 

(d) Technical progress on the recovery, reuse and destruction of ozone-depleting substances; 

(e) Accounting for: the production and use in various applications of ozone-depleting substances; 

ozone-depleting substances in inventories; ozone depleting substances in products; and the 

production and use in various applications of very short-lived substances; 

(f) Accounting of emissions of all relevant ozone-depleting substances with a view to updating 

continuously use patterns and co-ordinating such data with the Scientific Assessment Panel in 

order periodically to reconcile estimated emissions and atmospheric concentrations. 

Together with the Science and Environmental Effects Assessment reports, the 2010 TEAP Assessment 

Report -together with the 2010 TOC Assessment Reports- forms the direct response to the abovementioned decision. 

In the important Decision XIX/6 on the HCFC phase-out for developing countries, taken at MOP-19 in 

Montreal in September 2007, subparagraphs mention: 

“To encourage Parties to promote the selection of alternatives to HCFCs that minimize environmental 

impacts, in particular impacts on climate, as well as meeting other health, safety and economic 

considerations; 

 To agree that the Executive Committee, when developing and applying funding criteria for projects and 

programmes, and taking into account para 6, give priority to cost-effective projects and programmes 

which focus on, inter alia: 

1. Phasing-out first those HCFCs with higher ozone-depleting potential, taking into account 

national circumstances; 

2. Substitutes and alternatives that minimize other impacts on the environment, including on the 

climate, taking into account global-warming potential, energy use and other relevant factors; 

etc.” 
18 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

In Decision XX/8 on substitutes for HCFCs and HFCs, taken at MOP-20 in Doha, it is mentioned that 

more information on the HCFC and HFC substitution process is needed: 

“Recognizing that decision XIX/6 encourages Parties to promote the selection of alternatives to 

hydrochlorofluorocarbons to minimize environmental impacts, in particular impacts on climate, 

Recognizing also that there is scope for coordination between the Montreal Protocol and the United 

Nations Framework Convention on Climate Change and its Kyoto Protocol for reducing emissions and 

minimizing environmental impacts from hydrofluorocarbons, and that Montreal Protocol Parties and 

associated bodies have considerable expertise in these areas which they could share, 

Recognizing further that there is a need for more information on the environmental implications of 

possible transitions from ozone-depleting substances to high-global warming potential chemicals, in 

particular hydrofluorocarbons, 

1. To request the Technology and Economic Assessment Panel to update the data contained within the 

Panel’s 2005 Supplement to the IPCC/TEAP Special Report1

and to report on the status of 

alternatives to hydrochlorofluorocarbons and hydrofluorocarbons, including a description of the 

various use patterns, costs, and potential market penetration of alternatives no later than 15 May 

2009; 

2. To request the Ozone Secretariat to prepare a report that compiles current control measures, 

limits and information reporting requirements for compounds that are alternatives to ozonedepleting substances and that are addressed under international agreements relevant to climate 

change; etc. 

In Decision XXI/9 on substitutes for HCFCs and HFCs, taken at MOP-21 at Port Ghalib in Egypt, it is 

again mentioned that more information on the HCFC and HFC substitution process is needed: 

“Recalling that decision XIX/6 requests the Parties to accelerate the phase-out of production and 

consumption of hydrochlorofluorocarbons (HCFCs); 

Mindful of the need to safeguard the climate change benefits associated with phase-out of HCFCs; 

Aware of the increasing availability of low-Global Warming Potential (GWP) alternatives to HCFCs, in 

particular in the refrigeration, air-conditioning and foam sectors; 

Aware also of the need to appropriately ensure the safe implementation and use of low-GWP technologies 

and products; 

Recalling para 9 and 11 (b) of decision XIX/6; 

1. To request the Technology and Economic Assessment Panel (TEAP), in its May 2010 Progress Report 

and subsequently in its 2010 full assessment, to provide the latest technical and economic assessment of 

available and emerging alternatives and substitutes to HCFCs; and the Scientific Assessment Panel (SAP) 

in its 2010 assessment to assess, using a comprehensive methodology, the impact of alternatives to HCFCs 

on the environment, including on the climate; and both the SAP and the TEAP to integrate the findings in 

their assessments into a synthesis report; 

2. To request the Technology and Economic Assessment Panel in its 2010 progress report: 

(a) To list all sub-sectors using HCFCs, with concrete examples of technologies where lowGWP alternatives are used, indicating what substances are used, conditions of application, their 

costs, relative energy efficiency of the applications and, to the extent possible, available markets 

and percentage share in those markets and collecting concrete information from various sources 

including information voluntarily provided by Parties and industries. To further ask TEAP to 

compare these alternatives with other existing technologies, in particular, high-GWP technologies 

that are in use in the same sectors; 

 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 19

(b) To identify and characterize the implemented measures for ensuring safe application of 

low-GWP alternative technologies and products as well as barriers to their phase-in, in the 

different sub-sectors, collecting concrete information from various sources including information 

voluntarily provided by Parties and industries; 

(c) To provide a categorization and reorganization of the information previously provided in 

accordance with decision XX/8 as appropriate, updated to the extent practical, to inform the 

Parties of the uses for which low- or no-GWP and/or other suitable technologies are or will soon 

be commercialized, including to the extent possible the predicted amount of high-GWP 

alternatives to ozone-depleting substances uses that can potentially be replaced; 

3. To request the Ozone Secretariat to provide the UNFCCC Secretariat with the report of the 

workshop on high global-warming-potential alternatives for ozone-depleting substances; 

4. To encourage Parties to promote policies and measures aimed at avoiding the selection of highGWP alternatives to HCFCs and other ozone-depleting substances in those applications where other 

market-available, proven and sustainable alternatives exist that minimise impacts on the environment, 

including on climate, as well as meeting other health, safety and economic considerations in accordance 

with decision XIX/6; 

5. To encourage Parties to promote the further development and availability of low-GWP 

alternatives to HCFCs and other ozone-depleting substances that minimise environmental impacts 

particularly for those specific applications where such alternatives are not presently available and 

applicable; 

6. To request the Executive Committee as a matter of urgency to expedite the finalisation of its 

guidelines on HCFCs in accordance with Decision XIX/6; 

7. To request the Executive Committee, when developing and applying funding criteria for projects 

and programmes regarding in particular the phase-out of HCFCs: 

(a) to take into consideration paragraph 11 of decision XIX/6; 

(b) to consider providing additional funding and/or incentives for additional climate benefits where 

appropriate; 

(c) to take into account, when considering the cost-effectiveness of projects and programmes, the 

need for climate benefits; and 

(d) to consider in accordance with decision XIX/6, further demonstrating the effectiveness of low-GWP 

alternatives to HCFCs, including in Air Conditioning and refrigeration sectors in high ambient 

temperature areas in Article 5 countries and to consider demonstration and pilot projects in Air 

conditioning and refrigeration sectors which apply environmentally sound alternatives to HCFCs; 

8. To encourage Parties to consider reviewing and amending as appropriate, policies and standards 

which constitute barriers to or limit the use and application of products with low- or zero-GWP 

alternatives to ozone-depleting substances, particularly when phasing out HCFCs. 

The decisions as given above are based upon the perception that more actions are needed for the 

protection of the ozone layer, however, the emphasis in all relevant paragraphs is on the climate aspect 

of high-GWP ozone depleting substances, the high or possibly low-GWP replacements and their 

climate impact. In particular the above Decision XXI/9 mentions numerous times the development, 

availability, implementation and use of low-GWP alternatives to HCFCs, as well as a comparison with 

high-GWP alternatives. 

How the RTOC has been involved in the work of the Task Forces that addressed the requests by 

Parties in Decisions XX/8 and XXI/9 is given in section 1.2.
20 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

1.2 The UNEP Technology and Economic Assessment Panel 

Four Assessment Panels were defined in the original Montreal Protocol as signed 1987, i.e. 

Assessment Panels on (1) Science, and on (2) Environmental Effects, (3) a Technical Assessment and 

(4) an Economics Assessment Panel. The Panels were established in 1988-89; their Terms of 

Reference can be found in the Meeting Report of the 1st Meeting of the Parties, held in Helsinki in 

1989. Under the Technical Assessment Panel five Subsidiary Bodies, the so called Technical Options 

Committees were defined (see Meeting Report of the First Meeting of the Parties in Helsinki). The 

Technical and Economics Assessment Panels were merged after the Meeting in London in 1990 to the 

Technology and Economic Assessment Panel. At the Meeting in Copenhagen, it was decided that 

each Assessment Panel should have up to three co-chairs, with at least one from an Article 5 country. 

After the discussions on methyl bromide held at the meeting in Copenhagen, the Methyl Bromide 

Technical Options Committee was founded at The Hague in early 1993. From 1993 until 2001, the 

UNEP Technology and Economic Assessment Panel (TEAP) had 7 standing Technical Options 

Committees (TOCs). In 2001, the Economics Options Committee was disbanded, which resulted in a 

number of 6 Committees. In 2005, the Aerosols TOC and the Solvents TOC were disbanded, and a 

new Medical TOC and Chemicals TOC were formed by merging certain parts of the Aerosols and the 

Solvents TOC, and replenishing the membership with additional, new experts. Currently there are the 

following TOCs: 

1. Chemicals Technical Options Committee 

2. Flexible and Rigid Foams Technical Options Committee

3. Halons Technical Options Committee

4. Medical Technical Options Committee 

5. Methyl Bromide Technical Options Committee

6. Refrigeration, A/C and Heat Pumps Technical Options Committee 

Where, originally, the Panels were considered as the bodies that should carry out assessments pursuant 

to Article 6 under the Montreal Protocol (at least every four years), it is particularly the TEAP that has 

become a “standing advisory group” to the Parties on a large number of Protocol issues. The evolving 

role of the TEAP -and its Technical Options Committees and other temporary Subsidiary Bodies- can 

be explained by the fact that the focus of the Montreal Protocol has shifted from introducing and 

strengthening control schedules (based upon assessment reports) to the control of the use of controlled 

chemicals and to compliance with the Protocol. This implies the study of equipment, of use patterns, 

of trade, imports and exports etc. 

The Parties in Copenhagen took a number of decisions, which concern the work of the Technology 

and Economic Assessment Panel and its Committees. A decision (IV/13) on "Progress" requested the 

TEAP and its TOCs to annually report on progress in the development of technology and chemical 

substitutes. This decision was re-evaluated and restated in the meeting in Vienna, in 1995 (VII/34). 

As a result, progress reports have been conceived annually by the TEAP and its Committees; they 

were submitted to the Parties in the years 1996-2006 as part of the annual report of the TEAP (next to 

the progress reports, the annual reports deal with a large variety of issues on the basis of which Parties 

have taken certain decisions in the 1996-2006 period). 

In Vienna, the Parties also requested “to offer the assistance of the Scientific, Environmental Effects 

and Technology and Economic Assessment Panels to the SBSTA, the Subsidiary Body on Science and 

Technology under the United Nations Framework Convention on Climate Change (UNFCCC), as 

necessary” (VII/34). The SBSTA encouraged the Secretariat to continue its close collaboration with 

other relevant bodies such as the Technology and Economic Assessment Panel of the Montreal 

Protocol on Substances that Deplete the Ozone Layer, on technical and methodological issues.” In 

order to assess the status of the use of fluorochemicals, the IPCC and the TEAP organised a workshop 

in Petten, the Netherlands, in mid-1999. Output from this workshop was reported to the SBSTA in 

October 1999, before the UNFCCC Fifth Conference of the Parties (COP-5). Output was also used in 

the drafting of a TEAP report on HFCs and PFCs, which became available in October 1999. A new 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 21

decision on a study on the status of HFCs and alternatives to HFCs and PFCs, to be performed in 

2003-2004, was decided by the Parties to the UNFCCC in Delhi (COP-8) in 2002 and by the Parties to 

the Montreal Protocol in 2002 (MOP-14, Rome, Mirror Decision XIV/10). It asked for a joint 

undertaking by the Intergovernmental Panel on Climate Change (IPCC) and TEAP in order to prepare 

a Special Report on “Safeguarding the climate system and protecting the ozone layer; issues related to 

hydrofluorocarbons and perfluorocarbons”. A Steering Committee, consisting of six members (three 

IPCC Working Group co-chairs and the three TEAP co-chairs) has directed the Special Report study. 

The report (as well as a Technical Summary and a Summary for Policy Makers) has been adopted by 

governments in a Meeting in Addis Ababa, April 2005, and was published mid-2005. This Report has 

been the basis for many discussions that took place at the various Meetings of the Parties to the 

Montreal Protocol and the Kyoto Protocol. A Supplement Report to the Special Report was published 

in 2006 and contained a large amount of information on the size of banks and emissions in the 

different sectors, where refrigeration and air conditioning is actually the most important contributing 

sector. 

At the MOP-19 in Montreal an important Decision, Decision XIX/6 (as described in section 1.1), was 

taken on the accelerated phase-out of HCFCs in Article 5 countries. In the decision, a reduction 

schedule for production and consumption was defined for the period 2013-2030, with a freeze in 2013 

and a servicing tail until 2040. 

As a first consequence of Decision XIX/6, the Parties requested the TEAP and its RTOC in Decision 

XIX/8, to report on the status of substitutes and alternatives to HCFCs under high ambient conditions. 

The report was done by a Subcommittee of the RTOC, and submitted to Parties in a preliminary form 

in 2009 and in its final form in 2010. 

In 2008, Parties requested the TEAP and its committees, in Decision XX/8 (see above), to look at the 

status of alternatives in the different sectors and subsectors, as covered by the six Technical Options 

Committees. In a report by a Task Force, a large amount of material was summarised; this report also 

contained updated information on banks and emissions from all sectors, including refrigeration, AC 

and heat pumps as well as foams. In 2009, in Decision XXI/9 (see above), on HCFCs and 

environmentally sound alternatives, Parties requested the TEAP to update the information from the 

XX/8 report, and to report on the status of low GWP alternatives for the replacement of HCFCs, and to 

report on the comparison of performances of high and low GWP alternatives. TEAP established again 

a Task Force -having a large number of RTOC members-, which reported on the definition of the term 

“low-GWP” and “high-GWP”, and particularly on the 2009/2010 status of (low GWP) substitutes and 

alternatives to HCFCs in all sectors and subsectors. The information collected for this XXI/9 report 

has also been used in the preparation of the 2010 TOC Assessment Reports, including that of the 

RTOC. 

The 2010 Technical and Economic Assessment study has been carried out by the Technology and 

Economic Assessment Panel and its six Technical Options Committees. The six Committees consisted 

of more than 140 experts from a large number of countries (for a list, see the annex to the Technology 

and Economic Assessment Panel Report 2010). 

The 2010 Technical Options Committees consisted of several members of the 1998, 2002, and 2006 

Committees and additional new experts, to provide the widest possible international participation in 

the review. Much attention was again paid to adequate participation by technical experts from Article 

5 and CEIT countries, dependent upon budgetary constraints. The Technical Options Committee 

reports have been subject to a peer review before final release. The final version of the reports will be 

distributed internationally by UNEP and will also be available on the Internet 

(http://www.unep.org/ozone). 
22 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

1.3 The Technical Options Committee Refrigeration, A/C and Heat Pumps 

This Technical Options Committee Assessment Report on Refrigeration, A/C and Heat Pumps 

(hereafter called “RTOC Assessment Report”) also forms part of the UNEP review pursuant to Article 

6 of the Montreal Protocol. 

It is part of the 2010 assessment work of the Technology and Economic Assessment Panel (requested 

by the Parties in Montreal (XIX/20)). The information collected (particularly in the form of the the 

Executive Summaries) will also be part of the Technology and Economic Assessment Report 2010, as 

well as the overall 2010 Synthesis Report composed by the three Assessment Panel co-chairs, the 

beginning of 2011. 

The 2010 RTOC Assessment Report has been drafted in the form of a number of chapters. There are 

chapters on refrigerants and their properties, on the different R/AC application areas and one chapter 

on refrigerant conservation. The structure of the 2010 report was chosen similar to the structure of the 

2006 RTOC Assessment Report. 

Table 1-1: "Member countries" of UNEP's Refrigeration, A/C and Heat Pumps Technical 

Options Committee 

Austria 

Belgium 

Brazil 

China 

Czech Republic 

Denmark

France 

Georgia 

Germany 

India 

Jamaica 

Japan

Netherlands 

Norway 

Sweden 

United Kingdom 

United States

Each of the chapters was developed by 2-6 experts in the specific sector, and each chapter was chaired 

by a Chapter Lead Author - who did the larger part of the drafting and the co-ordination. The 2010 

RTOC included 29 representatives from Asian, European, Latin and North American companies, 

universities and governments, as well as independent experts (see Table 1-1). These representatives 

have been full (reporting) members; as resource persons the RTOC also had a small number of 

reviewing members (actually, only in a few chapters, e.g. chapters 2 and 9). 

Affiliations of the members are listed in Table 1-2 (29 organisations (including consultancies) were 

involved in the drafting of the report). The names and contact details of all members are given as an 

appendix to this RTOC Assessment Report. 

Several drafts of the report were made, reviewed by the separate chapters and discussed in five RTOC 

meetings (outline September 2008, preliminary draft March 2009, draft September 2009, peer review 

draft August 2010 and final report December 2010). A preliminary committee meeting was held in 

Copenhagen (back to back with an IIR meeting), September 2008. Drafting and reviewing meetings 

were held in Canada (Montreal), March 2009, Brazil (Sao Paulo), September 2009, Czech Republic 

(Prague), August 2010, and China (Hangzhou), December 2010. 

The report has been peer reviewed by a number of institutions and associations, each of them 

reviewing the different chapters sections in a co-ordinated effort in a tight timeframe, i.e., between the 

end of October and the end of November 2010 (see Table 1-3 for the peer review organisations 

involved). 

Peer review comments were collected and sorted out, and subsequently sent to all CLAs. They studied 

all peer review comments and made suggestions how to deal with the comments before the RTOC 

Meeting in December 2010. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 23

Table 1-2: Affiliations of the members of UNEP's Technical Options Committee on 

Refrigeration, A/C and Heat Pumps 

 

Braunschweig University Germany 

Calm, James M., Engineering Consultant U.S.A. 

Carrier Corporation U.S.A. 

Daikin Europe Belgium 

Danish Technological Institute Denmark 

Devotta, Sukumar, Independent Consultant India 

Paris Mines Tech, Ecole des Mines France 

FK Consultancy U.S.A. 

General Electric, Consumer Industrial, Retired U.S.A. 

heat AG / UHTC Austria/Germany 

Hill (Consultant) U.S.A. 

IEA Heat Pump Center Sweden 

Indian Institute of Technology Delhi India 

Ingersoll Rand Czech Republic 

Johnson Controls Denmark 

Johnson Controls USA 

Karlsruhe University of Applied Sciences Germany 

Maua Institute of Technology Brazil 

National Refrigeration Association, representative Georgia 

Nelson, private person Jamaica 

Panasonic Corporation Japan 

Re/genT b.v. Netherlands 

Re-phridge Consultancy United Kingdom 

SINTEF Energy Research, Trondheim Norway 

Star Refrigeration United Kingdom 

Technical University Eindhoven Netherlands 

The Trane Company U.S.A. 

U.S. Environmental Protection Agency U.S.A 

HAPI Consultancy, Joinville Brazil 

Zhejiang University, Hangzhou China 

The RTOC worked in chapter groups to address all peer review comments during the RTOC meeting 

in Hangzhou, China, December 2010. CLAs took note of how the groups decided to deal with the 

comments and whether or not to modify or amend the text; all suggestions were archived per chapter. 

CLAs then submitted the final chapters to the co-chairs. 

The final report was put together including Key Messages and an Abstract Executive Summary 

upfront, as well as Executive Summaries for all chapters (except chapter 11). UNEP’s Ozone 

Secretariat assisted in final formatting and heading style insertions. The report was then once more 

circulated to all RTOC members for a final check. 

The RTOC greatly acknowledges the voluntary involvement from the peer reviewers and the peer 

review institutions. 
24 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

Table 1-3: Institutions and organisations involved in the peer review of the 2010 RTOC report 

ACEA European Automobile Manufacturers' Association 

AHRI American Heating and Refrigeration Institute 

AIRAH Australian Institute of Refrigeration, Air conditioning and Heating 

ARAP Alliance for Responsible Atmospheric Policy 

CRAA Chinese Refrigeration and Air Conditioning Association 

CRT CRT Cambridge 

DKV German Refrigeration Association 

EIA Environmental Investigation Agency 

EHPA European Heat Pump Association 

EPEE European Partnership for Energy and Environment 

Greenpeace Greenpeace International 

IIAR International Institute for Ammonia Refrigeration 

IIR International Institute for Refrigeration 

IOR Institute of Refrigeration UK 

JAMA Japanese Automotive Manufacturer Association 

JRAIA Japanese Refrigeration and Air Conditioning Industry Association 

SAE Society of Automotive Engineers 

SAIRAC South African Institute for Refrigeration and Air Conditioning 

Shecco Shecco Brussels 

Transfrigoroute Transfrigoroute International 

Transicold Carrier Transicold 

1.4 Refrigeration, Air Conditioning and Heat Pumps 

1.4.1 General Remarks

Refrigeration, air conditioning and heat pump applications represent more than 70% of the ODS and 

replacement substances used; it is also one of the most important energy using sectors in the present 

day society. Estimates are difficult to give but as an average for the developed countries, its share in 

electricity use is thought to vary between 10 and 30%. 

The economic impact of refrigeration technology is much more significant than generally believed; 

300 million tonnes of goods are continuously refrigerated. While the yearly consumption of electricity 

may be huge, and where the investment in machinery and equipment may approach US$100,000 

million, the value of the products treated by refrigeration either alone will be four times this amount. 

This is one of the reasons that economic impacts of the phase-out of refrigerant chemicals (such as 

CFCs in the past, and HCFCs in Article 5 countries in the foreseeable future) have been and still are 

difficult to estimate. 

Refrigeration and air conditioning applications vary enormously in size and temperature level. A 

domestic refrigerator has an electrical input between 50-250 W and contains less than 30-150 g of 

refrigerant (dependent on the type of refrigerant), whereas industrial refrigeration and cold storage is 

characterised by temperatures between -10 C and -40 C, with electrical inputs up to several MW and 

refrigerant contents of many hundred kilograms. Air conditioning and heat pumps may show 

evaporation temperatures between 0 C and +10 C, significantly different from refrigeration 

applications, and vary enormously in size and input. 

In principle one can therefore discriminate between four main areas which each have subsectors: (i) 

the food chain in all its aspects, from cold storage via transport to domestic refrigeration, (ii) process 

air conditioning and refrigeration, (iii) comfort air conditioning, from air cooled equipment to water 

chillers, including heat pumps, and (iv) mobile air conditioning, with very specific, different aspects. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 25

This is one of the reasons that all the equipment is considered in this report in a large number of 

separate chapters or sections. 

Options and aspects for the refrigeration vapour compression cycle deserve most attention, since it is 

unlikely that during the next 10-20 years other principles will take over a substantial part of the 

market. In all application sectors described in the separate chapters in this report, most of the attention 

is focused on the vapour compression cycle. As stated, this cycle has so far provided a simple, 

economic, efficient and reliable way for refrigeration (this includes cycles using ammonia, carbon 

dioxide, fluorochemicals and hydrocarbons as refrigerants). 

The process of selecting a refrigerant for the vapour compression cycle is rather complex (not taking 

into account economic and costs aspects), since a large number of parameters need to be investigated 

concerning their suitability for certain designs, including: 

- thermodynamic and transport properties; 

- temperature ranges; 

- pressure ratios; 

- compressor requirements; 

- material and oil compatibility; 

- health, safety and flammability aspects; 

- environmental parameters such as ODP, GWP and atmospheric lifetime. 

These selection criteria were elaborated upon in various chapters of various UNEP RTOC Assessment 

Reports, and these selection criteria have not changed during the last years. Since then, it is the 

emphasis on the emissions of greenhouse gases that has increased; this can be directly translated to 

thermodynamic efficiency and quality of the equipment (leakage of refrigerant). 

The future of mankind, and his food supply in particular, depends on the availability of sufficient 

energy and on the availability of efficient refrigeration methods. Of course, this aspect must be more 

than balanced by a concern for the conservation of the biosphere, including in particular the global 

warming effect. Energy efficiency, therefore, is one of the most important aspects. 

1.4.2 Long Term Options and Energy Efficiency 

CFC production has been phased out since fifteen years in the developed countries, and the CFC 

phase-out in the developing countries has been completed by 2010. Where HCFCs have been largely 

phased out in the developed countries, the phase-out in the Article 5 countries is now asking full 

attention. In both developed and developing countries, HFCs have so far been important substitutes 

for CFCs and HCFCs. In many applications, alternatives to HCFCs have become commercially 

available, as pure HFCs, as blends of HFCs or as non-HFC alternatives. Therefore, HFCs have gained 

a large share of the replacement market. In particular the necessary incentives remain to be provided 

to Article 5 countries to transition from HCFCs to non-HCFC refrigerants, which will include both 

HFCs and non-fluorocarbon alternatives. 

It should be noted, however, that the changing refrigerant options are only part of the driving force for 

innovations in refrigeration and A/C equipment. Innovation is an ongoing independent process, which 

has to take into account all the environmental issues involved. 

In the long term, the role of non-vapour compression methods such as absorption, adsorption, Stirling 

and air cycles etc. may become more important; however, vapour compression cycles are thought to 

remain the most important candidates. 
26 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

For the long term, there remain, in fact, only five important different refrigerant options for the vapour 

compression cycle in all refrigeration and A/C sectors, listed alphabetically: 

• ammonia (R-717); 

• carbon dioxide (R-744); 

• hydrocarbons and blends (HCs, e.g. HC-290, HC-600a, HC-1270 etc.); 

• hydrofluorocarbons (HFCs, unsaturated HFCs (HFOs)); 

• water (R-718). 

None of the above mentioned refrigerants is perfect; all have both advantages and disadvantages that 

should be considered by governments, equipment manufacturers and equipment users. For instance, 

ammonia, carbon dioxide and hydrocarbons have negligible or low Global Warming Potentials 

(GWP), most HFCs have a relatively high GWP (this is not valid for the unsaturated HFCs (HFOs), 

which have a low GWP), ammonia is more toxic than the other options, and ammonia and 

hydrocarbons are flammable to certain extents. Appropriate equipment design, maintenance and use 

can address these concerns, though sometimes at the cost of greater capital investment or lower energy 

efficiency. 

The five refrigerant options above are in different stages of development or commercialisation. High 

GWP HFCs are widely applied in many sectors, ammonia and hydrocarbons enjoy growth in sectors 

where they can be easily accommodated, and for certain applications, CO2 equipment is being further 

developed and a large number of CO2 installations have been extensively tested on the market. 

Currently CO2 is gaining a substantial part of the supermarket refrigeration equipment market in 

certain regions. Water is used and may see some increase in use in limited applications. Work is 

being done by several committees in developing standards to permit the application of new 

refrigerants, and it is the intent of companies to reach world-wide accepted limits in those different 

standards. 

Similarly, energy efficiency research is partly spurred by the role of energy production in carbon 

dioxide emissions. Options for energy efficient operation of equipment form an important issue in 

each of the chapters of this 2010 RTOC Assessment report. 

The Framework Convention on Climate Change via its Kyoto Protocol as adopted in 1997 considers 

six important global warming gases in one basket (CO2, CH4, N2O, and the industrial gases HFCs, 

PFCs and SF6) using their respective Global Warming Potentials (GWP). The control process is based 

upon the control of equivalent global warming emissions via reductions. Of course, under the Kyoto 

Protocol, any national government is free to prioritise emission reductions, which in principle could 

also be done via a phase-out of HFC chemicals at a certain stage. On the contrary, it could also 

involve a certain growth in certain sectors in certain countries (e.g., the HFCs) which would have to be 

balanced by larger than average reductions in other greenhouse gas emissions. Although CFC and 

HCFC are not in the basket of Kyoto protocol, these are also significant warming impact gases. HFCs 

have similar GWP values than HCFCs but the GWPs of the CFCs are much higher. Insofar, the 

Montreal Protocol has been quite effective in reducing warming impacts during the CFC phase-out 

period. 

In the Special Report (IPCC TEAP, 2005) and its Supplement Report, as mentioned before, two 

scenarios were developed for the projections of the demand, banks and emissions of CFCs, HCFCs, 

HFCs and some PFCs (where these are used as replacements for ozone-depleting substances). 

Annually, the demand is defined as the amount of chemical required for use in a certain year, banks 

are equal to the different inventories of products, and the emissions are defined as the amount of 

chemical that is emitted during manufacturing, plus the amount emitted during the lifetime of the 

product (leakage from banks), plus the amount of chemical emitted at disposal. The activities 

underlying emissions of fluorocarbons are expected to expand significantly. These activities (such as 

the requirements for refrigeration, air conditioning and insulation) will involve a number of 

technologies. In non-Article 5 countries, the use and emissions of CFCs and HCFCs will decline and 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 27

stop as all obsolete equipment is retired. In Article 5 countries, ozone-depleting substances 

(particularly HCFCs) may be used for another one to two decades; a virtual phase-out has been 

decided for 2030 (Decision XIX/6). 

Current emission profiles are largely determined by historic use patterns, resulting in a still relatively 

high contribution (at present) from CFCs and HCFCs banked in equipment and foams. The largest 

bank of ODS (CFCs) is in foam products, which are located in the non-Article 5 countries. This will 

remain the case for the next few decades (see also the TEAP report on destruction and waste streams 

from the different sectors, by the Decision XX/7 Task Force). Banks of halons are also important, and 

are roughly split equally between non-Article 5 and Article 5 countries. The size of this bank is 

expected to decrease. It should be noted, that recovery efforts and the associated costs may vary 

widely, to the extent that certain, large amounts of ODS in banks are virtually unrecoverable, although 

still existing. However, the option for destruction still remains open. For example, refrigerants are 

generally considered to be easily recoverable but recovery of foam blowing agents can be more 

complicated (see again the report by the Decision XX/7 Task Force). 

In general, emissions, i.e., bank-turnover varies significantly from application to application: from 

months (e.g. solvents), several years (refrigeration applications) to over half a century (foam 

insulation). The banks stored in equipment and foams may leak during the use phase of the products 

they are part of, and at the end of the product life-cycle (in case they are not recovered or destroyed). 

1.4.3 Set up of the 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

The report has Key Messages and an Abstract Executive Summary (e.g. for policy makers), both of 

which were extracted from the Executive Summaries for all chapters, which are presented in the 

beginning of the report. Where the Executive Summaries were agreed by the separate chapters, the 

Key Messages and the Abstract Executive Summary were circulated numerous times to all CLAs and 

finally amongst Committee members until full agreement was reached. 

This chapter 1 gives a general introduction, and describes the process how the RTOC report was put 

together by the members. Chapter 2 presents refrigerants and all their aspects. It elaborates on Ozone 

Depleting Potentials, and on ODP and GWP data for reporting purposes. It also investigates the status 

and research needs for data, i.e., thermophysical, heat transfer, compatibility and safety data. 

Chapters 3, 4, 5 and 6 deal with the food chain and investigate the technical feasibility of options. 

They all consider non-ODP options and deal with aspects such as the use of non-fluorochemicals, the 

reduction of charges, energy efficiency improvements etc. Particularly the energy efficiency aspect 

plays an important role in chapter 3 on domestic refrigeration. Chapter 4 discusses the options for the 

3 types of commercial refrigeration equipment. Chapter 5 deals with industrial refrigeration and cold 

storage, chapter 6 with transport refrigeration. Chapters 7 and 8 deal with air-to-air air conditioning 

and heat pumps for water heating. Chapter 9 deals with the various aspects of chillers, which includes 

important considerations on energy efficiency. Chapter 10 describes the options for mobile air 

conditioning; it evaluates the potential the options unsaturated HFCs (HFOs), carbon dioxide, 

hydrocarbons and other options will have. Chapter 11 deals with refrigerant conservation in the 

broadest sense; via adequate practices one can reduce the emission of (ozone depleting and global 

warming) refrigerants to the atmosphere (recover and recycle, containment). 

The names and contact details of all RTOC members (CLAs and Co-authors) as well as the names of 

all Contributors from outside the RTOC are all given in Annex 1. 

In the last RTOC meeting in December 2010, the RTOC members also agreed to attach to the report 

an Extract of a 2009 report on demand, banks and emissions done by ADEME/ ARMINES (Denis 

Clodic, CLA Chapter 4 responsible). This report has been attached as Annex 2 for information 

purposes only, in order to expand on the banks and emissions information available in the separate 
28 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

chapters. This report in Annex 2 has no direct link to the separate chapters and has not been reviewed 

by the RTOC as a committee. It is therefore preceded by a disclaimer outlining this. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 29

Chapter 2 

__________________________________________________________ 

Refrigerants 

Chapter Lead Author 

James M. Calm 

Co-author (non-RTOC) 

Glenn C. Hourahan 

Contributors 

Dennis R. Dorman 

Mark O. McLinden 
30 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

2 Refrigerants 

More than 60 new refrigerants were commercialised for use either in new equipment or as service 

fluids (to maintain or convert existing equipment) since the 2006 assessment report. Of them, 21 

obtained standardised designations and safety classifications while the remainder are marketed with 

only proprietary identifiers (without public disclosure of compositions or without application for 

standardised designations). Most of the new refrigerants are blends containing hydrofluorocarbons 

(HFCs) or, in some cases, blends of HFCs and hydrocarbons (HCs). Additional refrigerants, including 

blend components, still are being developed to enable completion of scheduled phase-outs of ozonedepleting substances (ODSs). Significant focus is on alternatives, including blend components, 

offering lower global warming potentials (GWPs) to address climate change. That pursuit forces more 

attention than in the past on flammable – primarily low-flammability – candidates. Considerable 

effort continues for examination of broader use of ammonia (NH3, R-717), carbon dioxide (CO2, R744), and HCs as well as of blends of them or them with low-GWP HFCs. Additional research seeks 

to increase and improve the physical, safety, and environmental data for refrigerants, to enable 

screening, and to optimise equipment performance. 

Despite the number of new introductions, approximately 20 older and new refrigerants, some of them 

blends, constitute the majority of usage on a global basis. Even this number is likely to decline to 

approximately 10 or 12 as older equipment using ODSs or high-GWP options is retired, along with 

need for service fluids for them, and as manufacturers converge on preferred refrigerants for the 

future. 

2.1 Introduction 

This chapter discusses and provides tabular summaries for identifiers as well as physical, safety, and 

environmental data for refrigerants. It addresses the status of thermophysical (both thermodynamic 

and transport) property data and of ongoing examination of heat transfer and compatibility. This 

chapter does not address the suitability, advantages, and drawbacks of individual refrigerants or 

refrigerant groups for specific applications; such discussion is addressed for specific applications 

where relevant in subsequent chapters. 

2.1.1 Refrigerant Progression 

The historic progression of refrigerants encompasses four generations based on defining selection 

criteria /Cal08/: 

• 1830s-1930s – whatever worked: primarily familiar solvents and other volatile fluids including 

ethers, R-717, R-744, sulfur dioxide (SO2, R-764), methyl formate (HCOOCH3, R-611), HCs, 

water (H2O, R-718), carbon tetrachloride (CCl4, R-10), hydrochlorocarbons (HCCs), and others; 

many of them are now regarded as “natural refrigerants.” 

• 1931-1990s – safety and durability: primarily chlorofluorocarbons (CFCs), 

hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), ammonia, and water. 

• 1990-2010s – stratospheric ozone protection: primarily HCFCs (for transition use), HFCs, 

ammonia, water, hydrocarbons, and carbon dioxide. 

• 2010-? – global warming mitigation: still in determination, but likely to include refrigerants 

with very low or no ozone depletion potential (ODP), low global warming potential (GWP), and 

high efficiency; likely to include, at least initially, unsaturated hydrofluorocarbons 

(hydrofluoro-olefins, HFOs discussed below), ammonia, carbon dioxide, hydrocarbons, and 

water. 

GWP demarcation for acceptability is defined, at least initially, as having a GWP relative to CO2 for 

100 yr integration of 150 or less, predicated on European regulations for mobile air conditioning (see 

chapter 10). A proposed further classification scheme distinguishes between very low (or ultra-low) 

with GWP < ~30, very low with GWP < ~100, low with GWP < ~300, moderate with GWP < ~1000, 

high with GWP < ~3,000, very high with GWP < ~10,000, and ultra-high with GWP > ~10,000 

/UNEP10/. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 31

2.1.2 Unsaturated Hydrofluorochemicals 

Facing regulatory pressures to eliminate refrigerants with high GWPs, and at least for automobile 

systems GWPs exceeding 150, the major refrigerant manufacturers have aggressively pursued 

unsaturated fluorochemicals. They are chemicals consisting of two or more carbon atoms with at least 

one double bond between two or more of them as well as fluorine, hydrogen, and possibly also 

chlorine or other halogens. Unsaturated fluorocarbons also are identified as fluoro-alkenes or fluoroolefins. The double carbon-carbon bond(s) make(s) the compounds more reactive. That leads to rapid 

decomposition in the lower atmosphere, because such fluoro-alkenes are less stable in presence of the 

oxidative reactants there. Some also are subject to photolytic decomposition. The result is short 

atmospheric lifetimes and, thereby, very low ODPs and GWPs. 

The unsaturated HFC (also identified as hydrofluoro-alkene or hydrofluoro-olefin, HFO) family is a 

focal example with varying extents of fluorination, in part as a trade-off between flammability with 

low fluorine content and typically increasing GWP and cost with higher fluorine content. Chemical 

producers are pursuing alternatives for the most widely used low-, medium-, and high-pressure 

refrigerants. Among the unsaturated HFCs, various HFC-1225 isomers previously pursued seem 

abandoned predicated on toxicity findings. HFC-1234yf (CH2=CFCF3) in particular is being widely 

considered both as a single-compound refrigerant and as a blend component. Manufacturer 

announcements also indicate pursuit of HFC-1234ze(E) (CHF=CHCF3), HFC-1243zf (CH2=CHCF3), 

and other HFC-1234 and HFC-1243 isomers and enantiomers. Some manufacturers also are pursuing 

unsaturated HCFCs (also identified as hydrochlorofluoro-alkene or hydrochlorofluoro-olefins, 

HCFOs), notably HCFC-1233 isomers, to obtain similar benefits with reduced or avoided 

flammability, but they introduce a trade-off concern with ODP albeit extremely low. 

While complete data are not yet available, or publicly available due to the proprietary nature of 

development, the limited information already in the public domain suggests that some unsaturated 

hydrofluorochemicals will be technically and commercially viable. 

Opponents of unsaturated fluorochemicals argue, often vehemently, that they pose additional 

environmental or safety hazards not justified with existence of available “natural refrigerant” 

alternatives. The extent of long-term acceptability of unsaturated HFCs (HFOs) or more broadly 

unsaturated hydrohalochemicals is uncertain, though a number of initial studies indicate manageable 

environmental impacts /Leu10, Kaj10, Pap09/. 

The relatively recent commercial pursuit of unsaturated fluorochemicals, as well as blends of them or 

containing them, has catalyzed a number favourable claims but also counterclaims. More information 

is likely to emerge in the next assessment cycle. For now, the various application chapters that follow 

address consideration of specific unsaturated fluorochemicals as appropriate. Further information is 

likely to emerge in the next assessment cycle. 

2.2 Data Summary 

Table 2-1 provides summary data for refrigerants – both single-compound and blend – addressed in 

this report as well as those used historically, under consideration as candidates for future use, and 

undergoing renewed interest (historical and now candidates for broader application). The table 

excludes proprietary blends for which the composition (components) and/or formulation (their 

proportions) have not been disclosed. 

The table has been updated from prior assessments to reflect current data from consensus assessments 

and published scientific and engineering literature where possible. The summary table also adds two 

new single-compound refrigerants and 21 new blends introduced since the 2006 assessment report 

/UNEP06/. 

The data in this table were extracted from more extensive summaries by Calm and Hourahan /Cal07, 

Cal11/, the Refrigerant Database /Cal10/, and informatory appendices to ASHRAE Standard 34-2010 

/ASH10a/ and addenda thereto /ASH10b/. Those references provide further information on the 
32 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report

refrigerants included and address additional refrigerants. Some of the data have been updated with 

further revisions (later editions) of the cited sources, notably including REFPROP 9.0 /Lem10/ for 

thermophysical properties, though in some cases with updated fluid and mixture models for planned 

inclusion in future revisions. The database also identifies the sources for the data presented in the 

table as well as, for some refrigerants, additional data where conflicting values were reported by 

different investigators. The data and their limitations should be verified in the referenced source 

documents, particularly where use of the data would risk loss to life or property. REFPROP can be 

used to calculate additional properties for many of the refrigerants and additional blends. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 2-1: Physical, Safety, and Environmental Data for Historical, Current, and Candidate Refrigerants 
34 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 2-1: Physical, Safety, and Environmental Data for Historical, Current, and Candidate Refrigerants (continued) 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 2-1: Physical, Safety, and Environmental Data for Historical, Current, and Candidate Refrigerants (continued) 
36 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 2-1: Physical, Safety, and Environmental Data for Historical, Current, and Candidate Refrigerants (continued) 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 37

The data presented, from left to right in the table are: 

• refrigerant number, if assigned, in accordance with American Society of Heating, 

Refrigerating, and Air-Conditioning Engineers (ASHRAE) Standard 34 /ASH10a, 

ASH10b/: A revision to an international standard is in preparation, but not yet final, 

as the primary document for designation and safety criteria /ISO05b, ISO08/, but the 

proposed designation systems are essentially consistent. 

• chemical formula, in accordance with the International Union of Pure and Applied 

Chemistry (IUPAC) convention /IUP79/ or, for blends, the blend composition in 

accordance with ASHRAE Standard 34 /ASH10a, ASH10b/ 

• molecular mass calculated /Cal11/ based on the updated IUPAC atomic weights 

/Wie09/ 

• normal boiling point (NBP) or, for blends, the bubble point temperature at 101.325 

kPa based on REFPROP 9.0 /Lem10/ when included 

• critical temperature (Tc) in °C or, for blends, the calculated pseudo-critical 

temperature based on REFPROP 9.0 /Lem10/ when included 

• Occupational Exposure Limit (OEL) such as the Threshold Limit Value (TLV) in 

ppm v/v assigned by the American Conference of Governmental Industrial 

Hygienists (ACGIH), Workplace Environmental Exposure Level (WEEL) by the 

American Industrial Hygiene Association (AIHA), or a consistent occupational 

exposure limit on a time-weighted average (TWA) basis for an 8 to 10 hr day and 40 

hr work week 

• lower flammability limit (LFL) in % concentration ambient air: Where evident, the 

tabulated values are those determined in accordance with ASHRAE Standard 34 

/ASH10a, ASH10b/. 

• safety classification, if assigned, in accordance with ASHRAE Standard 34 

/ASH10a, ASH10b/: The leading letters A and B signify “lower” and “higher” 

toxicity, respectively, based on occupational exposure limits. The numbers 1, 2, and 

3 indicate “no flame propagation,” “lower flammability,” and “higher flammability,” 

respectively, at specified test conditions predicated on both LFL and heat of 

combustion. wff signifies that the worst case of formulation and the worst case of 

fractionation for flammability, respectively, both as defined in /ASH10a/, is 

flammable in either the vapour or liquid phase. A recent modification to ASHRAE 

34, also proposed for International Organization for Standardization (ISO) 817 

/ISO08/, subdivides group 2 based on the burning velocity, with 2L implying those 

more difficult to ignite /ASH10a/. Some of the classifications are followed or 

replaced by lower case letters that indicate: 

d a prior classification was deleted and the refrigerant no longer has a safety 

classification 

p a classification assigned on a provisional basis 

r a recommended revision or addition as shown, but pending final approval 

and/or publication 

• atmospheric lifetime (τatm) in years: Note that τatm normally is not indicated for 

blends since it is ambiguous whether the lifetime pertains to the blend as formulated, 

a modified formulation as some components decompose more rapidly than others, or 

the most enduring component. 

• ozone depletion potential (ODP) relative to CFC-11: ODPs indicate the relative 

ability of refrigerants (and other chemicals) to destroy stratospheric ozone. The 

values included reflect the latest scientific consensus data as adopted in the Scientific 

Assessment /WMO10/. Additional, consistent ODP data are included as available 

from references Cal10 and Cal11 for refrigerants for which consensus ODPs were 

not adopted. The ODPs indicated for blends are calculated mass-weighted averages 

/Cal10, Cal11/ based on the latest accepted IUPAC atomic weights /Wie09/ for the 

components. 

• global warming potential (GWP) relative to CO2 for 100 year integration based on 

the values reported in the IPCC Fourth Assessment Report /IPCC07/ and the 
38 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Scientific Assessment /WMO10/. The values shown are direct GWPs; indirect and 

net GWPs are discussed in references IPCC07 and WMO10. Additional, consistent 

GWP data are similarly included as available from references Cal10 and Cal11 for 

refrigerants for which consensus GWPs were not adopted. The GWPs indicated for 

blends are calculated mass-weighted averages /Cal10, Cal11/ based on the latest 

accepted IUPAC atomic weights /Wie09/ for the components. The GWP values 

shown as “~20” or “<20” in Table 2-1 for hydrocarbons reflect uncertainty in 

calculation, for which there is no scientific consensus at this time. The 

approximations shown lie in the ranges of uncertainty. 

• status: Refrigerants restricted (production limitations, phaseout, or measures to 

reduce releases) for environmental reasons are noted as follows: 

M controlled (or for blends one or more components is controlled) under the 

Montreal Protocol 

K controlled (or for blends one or more components is controlled) under the 

Kyoto Protocol 

2.2.1 Ozone Depletion Potentials 

The ODPs indicated in the Table 2-1 are semi-empirical values except for HCFC-123, for 

which a model-derived value was adopted in scientific assessments due to its short 

atmospheric lifetime /WMO10/. Semi-empirical ODPs are calculated values that incorporate 

adjustments for observed atmospheric measurements. This approach is conceptually more 

accurate than other measures, but the data needed are difficult to measure precisely and it is 

still evolving with further and improved measurements and understanding. There are other 

ODP indices, among them modelled, time-dependent, and regulatory variants /Cal07, Cal11/. 

Modelled data are determined by large models that calculate impacts based on decomposition 

paths and rates as well as atmospheric conditions including the influences of additional ozone 

depleting substances. Time-dependent ODPs use chemicals other than CFC-11 as the 

reference to emphasise impacts for other, typically shorter, timeframes. Normalising values 

to short-lived compounds accentuates near-term impacts, but discounts long-term effects. 

Time-dependent ODPs are not cited often, particularly since the release of ozone-depleting 

substances already has peaked and recovery of the stratospheric ozone layer is underway. 

Regulatory ODPs generally are old data used to set phase-out steps, determine compliance 

with the Montreal Protocol, and allocate production quotas in national regulations. Because 

of the political and competitive complexities in changing consumption targets and production 

allocations, these values commonly are left unchanged even when newer scientific findings 

improve the quantification precision. The ODP values listed in the annexes to the Montreal 

Protocol, for example, have not been updated since 1987 for chlorofluorocarbons (CFCs) and 

1992 for hydrochlorofluorocarbons (HCFCs). A note in the Protocol indicates that the values 

“are estimates based on existing knowledge and will be reviewed and revised periodically,” 

but that has not happened yet /UNEP09/. 

2.2.2 ODP and GWP Data for Regulatory and Reporting Purposes 

The ODP and GWP data presented in Table 2-1 are based on international scientific 

assessments and reflect the latest consensus determinations on potential impacts. However, 

the reduction requirements and allocations under the Montreal Protocol, emission reductions 

and reporting pursuant to the Kyoto Protocol, and provisions in many national regulations 

pursuant to them use older, adopted values. 

Table 2-2 compares the latest consensus ODP data /WMO10/ to the “regulatory” ODPs used 

in the Montreal Protocol /UNEP09/. Table 2-3 similarly contrasts the latest consensus GWPs, 

for 100 yr integration, with those used for reporting and emission reductions under the Kyoto 

Protocol (from /IPCC95/). 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 39

Table 2-2: Scientific and Regulatory ODPs 

for BFC, CFC, and HCFC Refrigerants 

 ODP 

refrigerant scientific a regulatory 

 11 1.0 1.0 

 12 0.82 1.0 

 12B1 7.9 3.0 

 13 1.0 

 13B1 15.9 10.0 

 21 0.04 

 22 0.04 0.055 

 113 0.85 0.8 

 114 0.58 1.0 

 115 0.57 0.6 

 123 0.01 0.02 

 124 0.02 0.022 

 142b 0.06 0.065 

a

 ODPs indicated are as adopted in reference 

/WMO10/. They are semi-empirical except 

for HCFC-123, which is a modelled value 

(0.0098) based on its short atmospheric 

lifetime. 

Table 2-3: Current Consensus and Reporting GWPs 

for 100 yr Integration for HFC and PFC Refrigerants 

 GWP 

refrigerant /WMO10/ reporting 

14 7,390 6,500

23 14,200 11,700

32 716 650

116 12,200 9,200

125 3,420 2,800

134a 1,370 1,300

143a 4,180 3,800

152a 133 140

218 8,830 7,000

227ea 3,580 2,900

 236fa 9,820 6,300

 C318 10,300 8,700

744 1 1
40 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

2.3 Status and Research Needs for Data 

2.3.1 Thermophysical Properties 

The status of data for the thermophysical properties of refrigerants, which include both 

thermodynamic properties (such as density, pressure, enthalpy, entropy, and heat capacity) 

and transport properties (such as viscosity, thermal conductivity, and surface tension), is 

generally good. The data are sufficient to permit evaluation and testing of virtually all 

candidate refrigerants, with notable exception for the newer unsaturated hydrofluorochemicals 

(see §2.1.2 above). Data gaps do exist, however, for the thermodynamic and transport 

properties of blends and less-common fluids. 

The thermodynamic data and models for the most-common HFCs (HFC-32, HFC-125, and 

HFC-134a) and HFC blends (R-404A, R-407C, R-410A, and R-507A) are generally 

excellent. The data often are limited for new blends. The transport data for these fluids are 

good for the single-compound refrigerants, but additional data and improved models are 

needed for the HFC and some HC blends. The thermodynamic data for HC-290 (propane), 

HC-600 (n-butane), and HC-600a (isobutane) are generally very good. The data for R-717 

(ammonia) are not as good as commonly assumed; much of the data are old and sometimes 

inconsistent and/or limited in coverage. The property data for R-744 (carbon dioxide) are 

excellent. 

An international standard provides thermodynamic properties of ten single-compound 

refrigerants and four blends /ISO05a/. The U.S. National Institute of Standards and 

Technology (NIST) REFPROP database /Lem10/ implements and provides references to 

published models for the thermodynamic and transport properties of all of the most common 

refrigerants and blends. It calculates properties over wide ranges of temperature, pressure, 

and composition, and it is compliant with the ISO standard /ISO05a/. 

The data situation for the less-common fluids is more variable. There is interest in the ethers 

and particularly the hydrofluoroethers (HFEs) /Biv97, Sek00/. The available data for them 

are often scattered among obscure sources. There is a need to collect and evaluate the data for 

such candidates. 

Properties are beginning to emerge for unsaturated HFCs /for example Bro09a, Bro09b, 

Din10, Gre09, Hig10, Kay10, McL10, Ric10, Tan09 and Tan10/ and further studies are 

underway. Two such refrigerants were added to REFPROP 9.0 in 2010 /Lem10/. 

A major uncertainty for all of the refrigerants is the influence of lubricants on heat transfer 

and other properties. The working fluid in most systems is actually a mixture of the 

refrigerant and the lubricant carried over from the compressor(s). Research on the refrigerantlubricant mixtures is underway. It is complicated by the great variety of lubricants in use and 

by the often highly proprietary nature of the chemical structure or compositions of the 

lubricant and/or additives. In addition to impacting properties themselves (and especially 

viscosity and heat transfer), lubricant selections, properties, and degradation have substantial 

impacts on equipment wear that in-turn alters performance from predictions based on 

refrigerant properties. 

2.3.2 Heat Transfer and Compatibility Data 

Refrigerant heat transfer technology has been extensively studied and documented by 

researchers in many countries. Two reports by Thome /Tho98a and Tho98b/ provide 

comprehensive reviews of evaporating and condensing heat transfer for many refrigerants 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 41

including fluorochemicals, hydrocarbons, ammonia, and carbon dioxide. The reports cover 

in-tube and shell-side boiling and condensing of single-compound refrigerants, azeotropic and 

zeotropic blends, and refrigerant-lubricant mixtures. They address plain tubes, internally 

finned tubes with conventional and cross-grooved fins, and both conventional low-fin and 

enhanced externally-finned tubes plus falling-film evaporation. Other reviews for refrigerant 

heat transfer technology include Ohadi et al. /Oha96/ for ammonia, Pais and Webb /Pai91/ for 

pool boiling on enhanced surfaces, Cavallini et al. /Cav95/ for condensation models of 

refrigerants inside smooth and enhanced tubes, Darabi et al. /Dar95/ for flow boiling 

correlations in smooth and augmented tubes, Singh et al. /Sin95/ on electrohydrodynamic 

enhancement of heat transfer, and a series of articles on heat transfer of carbon dioxide, 

ammonia, and hydrocarbons /IIR97/. 

Many types of refrigeration and air-conditioning systems are operating with fluorochemical, 

hydrocarbon, ammonia, and carbon dioxide refrigerants, suggesting reasonably adequate 

refrigerant heat transfer data. The best heat transfer data availability are for fluorocarbon 

(now mainly HFCs) and ammonia refrigerants. From the above-mentioned reports, plus input 

from other researchers, the following research needs were determined: 

 further test data for shell-side boiling and condensation of zeotropic mixtures 

 local heat transfer data determined at specific values of vapour quality 

 microchannel heat exchanger refrigerant-side heat transfer data including flow 

distribution effects 

 effects of lubricants on heat transfer, especially for ammonia, carbon dioxide, 

hydrocarbons, unsaturated HCFCs, and unsaturated HFCs 

 accurate plain tube and microfin tube evaporation and condensation data for 

hydrocarbons 

 inside-tube condensation heat transfer data for carbon dioxide at low 

temperatures such as –20 °C 

 heat transfer correlations for carbon dioxide supercritical heat rejection and twophase evaporation 

Materials compatibility data are available from many sources, among them manufacturers’ 

literature (refrigerant, plastics, and elastomer manufacturers), materials chemical resistance 

publications, and a series of studies performed for the Materials Compatibility and Lubricants 

Research (MCLR) Program of the Air-Conditioning and Refrigeration Technology Institute 

(ARTI). The MCLR reports addressed compatibility of refrigerants and lubricants with 

metals, hermetic motor materials, elastomers, engineering plastics, desiccants, and lubricant 

additives /Cav93, Cav97, Doe93, Doe96, Fie95, Ham94, and Hut92/. The MCLR studies 

focused primarily on fluorochemical replacements for CFCs via sealed-tube and other 

laboratory tests. In general, HFCs were found to be less reactive than HCFCs such as HCFC22 or HCFC-123. As a result, most materials accepted as compatible with HCFCs also were 

deemed compatible with HFCs. A statistical study of compressors identified air as the most 

aggressive contaminant, forming oxidised lubricant products, based on tests for non-ideal 

contaminant conditions (with added water, air, and organic acids) /Cav00/. Additionally, 

water and acid development with air affected overall mechanical performance /Cav00/. The 

study suggests that further compatibility studies may be needed for non-ideal conditions. 

While actual data are as yet very limited, unsaturated halochemicals (for example unsaturated 

HFCs – HFOs) may be less thermally stable at compressor operating temperatures. Limited 

studies report favourable stability in anhydrous, air free, sealed tube tests /Lec09/, but 

decomposition or corrosion effects – particularly in the presence of common contaminant 

levels in actual systems – need further study. 
42 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

A major source of materials compatibility data for carbon dioxide, ammonia, and 

hydrocarbons are three chemical resistance guides by Pruett covering metals, elastomeric 

compounds, and engineering plastics /Pru83, Pru94, and Pru95/. Since plastics and 

elastomers contain many types of additives (most of them proprietary), specific materials 

should be tested to ensure compatibility. 

Ammonia is incompatible with most types of electrical wiring insulation. Metals inside 

ammonia systems normally are limited to stainless and carbon steel, but two publications 

from Germany /Kna97 and Lip97/ report good compatibility of ammonia with copper and 

copper alloys in systems with careful moisture control, as water intrusion can result in severe 

copper corrosion. Aluminium is compatible with pure (dry) ammonia, but it is sensitive to 

corrosion in water circuits due to the presence of chlorides. Aqueous solutions of ammonia 

cause corrosion that puts aluminium components at risk, but coatings may offer corrosion 

prevention /Eur00/. Further study is needed to determine the precise levels of moisture of 

concern with consideration of the dissimilar levels of hygroscopicity of different lubricants. 

A materials issue with carbon dioxide is explosive decompression with elastomers, especially 

in systems with pressure cycling. Carbon dioxide is very soluble in many types of elastomers, 

and if it cannot diffuse out of the elastomer quickly enough, bubbles of gas may grow and 

cause rupture of the elastomer shapes, such as o-ring seals. Explosive decompression can be 

minimised by selecting elastomers with appropriate mechanical properties and tear strength, a 

low carbon dioxide solubility coefficient, and a high carbon dioxide diffusion coefficient 

/Har99/. 

Sealed tube tests containing HC-290 (propane) and HC-600a (isobutane) with various oils, 

materials, and air show negligible degradation /San96/. In further sealed tube tests, a variety 

of elastomers were tested with an R-290/600a blend or HC-601 (n-pentane) with a mineral or 

polyolester (POE) oil; Buna N, hydrogenated nitrile butadiene rubber (HNBR), Viton, and 

neoprene performed well while natural, silicon, and ethylene propylene diene terpolymer 

(EPDM) rubbers were less suitable /Col00/. Impurities at the level of 3% in HC-290 were 

found to not affect performance within measurement uncertainties, provided that the levels of 

sulfur, water, and unsaturated hydrocarbons were strictly limited /Kru97/. 

2.3.3 Safety Data 

The primary hazards from refrigerant handling and use arise from pressure explosions, 

toxicity, flammability, and air displacement, the last of which may lead to oxygen deprivation 

and asphyxiation /Cal94/. 

Pressure data are generally well characterised as necessary for component and system design. 

Safety standards such as American National Standards Institute / American Society of 

Heating, Refrigerating, and Air-Conditioning Engineers (ANSI/ASHRAE) 15, Safety 

Standard for Refrigeration Systems /ASH10c/, which is the basis of many national and 

international standards and regulations, provide guidance on vessel requirements, pressure 

relief devices, and testing. 

Toxicity concerns arise from both accidental releases and occupational handling, for example 

to install, service, and remove equipment /Cal94 and Cal96/. The data are divided into acute 

(short-term, single exposure) and chronic (long-term, possibly repeated exposure). Key acute 

effects include lethality, cardiac sensitisation, central nervous system (CNS) or anesthetic 

effects, and others that may impair the ability to escape or cause permanent injury. Most of 

these effects arise from inhalation rather than contact or ingestion, since a desirable attribute 

of refrigerants is that they be volatile compounds and, as a result, either are vapours at typical 

conditions or vaporise quickly in contact with body temperatures. Accordingly, it is hard to 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 43

have extended contact or to ingest sufficient quantities before inhalation effects come into 

play. Exceptions are refrigerants that irritate or corrode the skin. 

Safety data and resulting recommendations for refrigerant concentration limits and 

occupational exposure limits generally are available for fluorochemical refrigerants /Cal00, 

Cal07, and Cal10/. The data typically are developed, primarily through animal testing, by 

manufacturers in the course of qualifying new candidates. A collaborative effort among 

manufacturers, the Programme for Alternative Fluorocarbon Toxicity Testing (PAFT), 

developed extensive data for new fluorochemical replacements for CFCs /PAF95 and 

PAF96/. 

Data are less readily available for hydrocarbons and generally are sparse for exposures above 

fire hazard concentrations, though toxic effects from hydrocarbons generally are not manifest 

below them /Kir76/. The risks inherent to testing flammable mixtures and historical 

presumption that application exposures will be kept below the LFL both mitigate against 

testing higher concentrations. 

Extensive data are available for ammonia /Cle90 and Syr90/ and carbon dioxide /NIO76/, 

though much of it predates currently accepted toxicity test criteria and results in conflicts 

from early tests with primitive laboratory methods and contaminated samples. 

Further data are needed for fluoroether and hydrofluoroether candidates /Biv97 and Sek00/ 

and for unsaturated fluorochemicals. 

Flammability data generally are available /Ric92, Cal07, ASH10a/, though data dispersion 

from different test methods and laboratories leads to a degree of uncertainty in some cases. 

2.4 References 

/ASH10a/ Designation and Safety Classification of Refrigerants, ANSI/ASHRAE Standard 34-2010, 

American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), 

Atlanta, GA, USA, 2010 

/ASH10b/ Designation and Safety Classification of Refrigerants, ANSI/ASHRAE Addenda a, b, and 

d to ANSI/ASHRAE Standard 34-2010, American Society of Heating, Refrigerating, and 

Air-Conditioning Engineers (ASHRAE), Atlanta, GA, USA, 2010 

/ASH10c/ Safety Standard for Refrigeration Systems, ANSI/ASHRAE Standard 15-2010, American 

Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), Atlanta, 

GA, USA, 2010 

/Biv97/ D. B. Bivens and B. H. Minor, “Fluoroethers and Other Next-Generation Fluids”, 

Refrigerants for the 21st Century (proceedings of the ASHRAE/NIST Refrigerants 

Conference, Gaithersburg, MD, 6-7 October 1997), American Society of Heating, 

Refrigerating, and Air-Conditioning Engineers (ASHRAE), Atlanta, GA, USA, 122-134, 

1997; International Journal of Refrigeration, 21(7):567-576, 1998 

/Bro09a/ J. S. Brown, C. Zilio, and A. Cavallini, “Estimations of the Thermodynamic and Transport 

Properties of R-1234yf Using a Cubic Equation of State and Group Contribution 

Methods,” Proceedings of the 3rd IIR Conference on Thermophysical Properties and 

Transfer Processes of Refrigerants (Boulder, CO, USA, June 23-26, 2009), International 

Institute of Refrigeration, Paris France, and the National Institute of Standards and 

Technology (NIST), Boulder, CO, USA, paper 127, June 2009 

/Bro09b/ J. S. Brown, “HFOs: New, Low Global Warming Potential Refrigerants,” ASHRAE 

Journal, 51(8):22-29, August 2009 

/Cal94/ J. M. Calm, “Refrigerant Safety,” ASHRAE Journal, 36(7):17-26, July 1994 
44 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

/Cal96/ J. M. Calm, “The Toxicity of Refrigerants,” Proceedings of the 1996 International 

Refrigeration Conference at Purdue (23-26 July 1996), Purdue University, West Lafayette, 

IN, USA, 157-162, July 1996 

/Cal00/ J. M. Calm, “Toxicity Data to Determine Refrigerant Concentration Limits,” report 

DOE/CE/23810-110, Air-Conditioning and Refrigeration Technology Institute (ARTI), 

Arlington, VA, USA, September 2000 

/Cal07/ J. M. Calm and G. C. Hourahan, “Refrigerant Data Summary Update,” HPAC Engineering, 

79(1):50-64, January 2007 

/Cal08/ J. M. Calm, “The Next Generation of Refrigerants — Historical Review, Considerations, 

and Outlook,” International Journal of Refrigeration, 31(7):1123-1133, November 2008 

/Cal10/ J. M. Calm, “Refrigerant Database,” Air-Conditioning and Refrigeration Technology 

Institute (ARTI), Arlington, VA, USA, July 2001 and unpublished updates thereto though 

2010 

/Cal11/ J. M. Calm and G. C. Hourahan, “Physical, Safety, and Environmental Data Summary for 

Current and Alternative Refrigerants,” Proceedings for the 23rd International Congress of 

Refrigeration (Prague, Czech Republic, 21-26 August 2011), International Institute of 

Refrigeration (IIR), Paris, France, 2011 (in preparation) 

/Cav93/ R. C. Cavestri, “Compatibility of Refrigerant and Lubricants with Engineering Plastics”, 

report DOE/CE/23810-15, Air-Conditioning and Refrigeration Technology Institute, 

Arlington, VA, USA, September 1993, revised December 1993 

/Cav95/ A. Cavallini et al., “Condensation of New Refrigerants Inside Smooth and Enhanced 

Tubes,” Proceedings of the 19th International Congress of Refrigeration (The Hague, The 

Netherlands, 20-25 August 1995), International Institute of Refrigeration (IIR), Paris, 

France, IVa:105-114, 1995 

/Cav97/ R. C. Cavestri et al., Compatibility of Lubricant Additives with HFC Refrigerants and 

Synthetic Lubricants (Final Report, Part 1), report DOE/CE/23810-76, Air-Conditioning 

and Refrigeration Technology Institute, Arlington, VA, USA, July 1997 

/Cav00/ R. C. Cavestri, Effect of Selected Contaminants in Air Conditioning and Refrigeration 

Equipment (Final Report), report ARTI MCLR DOE/CE/23810-111, Air-Conditioning and 

Refrigeration Technology Institute, Arlington, VA, USA, 2000 

/Cle90/ Clement Associates, Incorporated, Health Effects Assessment for Ammonia, The Fertilizer 

Institute, Washington, DC, USA, February 1990 

/Col00/ D. Colbourne and T. J. Ritter, “Compatibility of Non-Metallic Materials with Hydrocarbon 

Refrigerant and Lubricant Mixtures,” Proceedings of the 4th IIR-Gustav Lorentzen 

Conference Natural Working Fluids (25-28 July 2000), Purdue University, West Lafayette, 

IN, USA, 395-400, 2000 

/Dar95/ J. Darabi, M. Salehi, M.H. Saeedi and M. M. Ohadi, “Review of Available Correlations for 

Prediction of Flow Boiling Heat Transfer in Smooth and Augmented Tubes,” paper CH95-12-2, Transactions (Winter Meeting, Chicago, IL, USA, 28 January – 1 February 

1995), American Society of Heating, Refrigeration, and Air-Conditioning Engineers, 

Atlanta, GA, USA, 101(1):965-975, 1995 

/Din10/ G. Di Nicola, M. Pacetti, F. Polonara, and G. Santori, “P−V−T Behavior of 2,3,3,3-

Tetrafluoroprop-1-ene (HFO-1234yf) in the Vapor Phase from 243 to 373 K,” Journal of 

Chemical and Engineering Data, 55(9):3302–3306, 2010 

/Doe93/ R. G. Doerr and S. A. Kujak, “Compatibility of Refrigerants and Lubricants with Motor 

Materials,” report DOE/CE/23810-13, Air-Conditioning and Refrigeration Technology 

Institute, Arlington, VA, USA, May 1993 

/Doe96/ R. G. Doerr and T. D. Waite, “Compatibility of Refrigerants and Lubricants with Motor 

Materials under Retrofit Conditions,” report DOE/CE/23810-63, Air-Conditioning and 

Refrigeration Technology Institute, Arlington, VA, USA, October 1996 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 45

/Eur00/ Eurammon, Aluminum as Construction Material in Ammonia Refrigeration Cycles, 

information bulletin 10, Frankfurt, Germany, 2000.01 

/Fie95/ J. E. Field, “Sealed Tube Comparisons of the Compatibility of Desiccants with 

Refrigerants and Lubricants,” report DOE/CE/23810-54, Air-Conditioning and 

Refrigeration Technology Institute, Arlington, VA, USA, May 1995 

/Gre09/ A. J. Grebenkov, R. Hulse, H. Pham, and R. Singh, “Physical Properties and Equation of 

State for Trans-1,3,3,3-Tetrafluoropropene,” Proceedings of the 3rd IIR Conference on 

Thermophysical Properties and Transfer Processes of Refrigerants (Boulder, CO, USA, 23-

26 June 2009), paper 191, International Institute of Refrigeration, Paris France, and the 

National Institute of Standards and Technology (NIST), Boulder, CO, USA, June 2009 

/Ham94/ G. R. Hamed, R. H. Seiple, and O. Taikum, “Compatibility of Refrigerant and Lubricants 

with Elastomers,” report DOE/CE/23810-14, Air-Conditioning and Refrigeration 

Technology Institute, Arlington, VA, USA, January 1994 

/Har99/ C. Harrison, “Keeping CO2 Where It Belongs. Requirements for Sealing Future 

Automotive Climate Control Systems,” Meeting Results and Presentations, SAE 

International Automotive Alternate Refrigerant Systems Symposium, Scottsdale, AZ, 

USA, 28 June – 1 July 1999 

/Hig10/ Y. Higashi, “Thermophysical Properties of HFO-1234yf and HFO-1234ze(E),” 

Proceedings of the International Symposium on Next-Generation Air Conditioning and 

Refrigeration Technology (Tokyo, Japan), New Energy and Industrial Technology 

Development Organization (NEDO), Kawasaki City, Kanagawa Prefecture, Japan, 

February 2010 

/Hut92/ D. F. Huttenlocher, “Chemical and Thermal Stability of Refrigerant-Lubricant Mixtures 

with Metals,” report DOE/CE/23810-5, Air-Conditioning and Refrigeration Technology 

Institute, Arlington, VA, USA, 9 October 1992 

/IIR97/ Heat Transfer Issues in Natural Refrigerants (proceedings of the IIR Conference – meeting 

of Commissions B1, E1, and E2, University of Maryland, College Park, MD, USA, 6-7 

November 1997), publication 1997/5, International Institute of Refrigeration, Paris, France, 

1997 

/IPCC95/ Intergovernmental Panel on Climate Change (IPCC) of the World Meteorological 

Organization (WMO) and the United Nations Environment Programme (UNEP), “Climate 

Change 1995 — Contribution of Working Group I to the Second Assessment Report of the 

Intergovernmental Panel on Climate Change,” edited by J. T. Houghton, L. G. Meira Filho, 

B. A. Callander, N. Harris, A. Kattenberg, and K. Maskell, Cambridge University Press, 

Cambridge, UK, 1996 

/IPCC05/ Intergovernmental Panel on Climate Change (IPCC) and the Technology and Economic 

Assessment Panel (TEAP), Safeguarding the Ozone Layer and the Global Climate System: 

Issues Related to Hydrofluorocarbons and Perfluorocarbons, World Meteorological 

Organization (WMO), Geneva, Switzerland, and the United Nations Environment 

Programme (UNEP) Ozone Secretariat, Nairobi, Kenya, 2005 

/IPCC07/ Intergovernmental Panel on Climate Change (IPCC) of the World Meteorological 

Organization (WMO) and the United Nations Environment Programme (UNEP), “Climate 

Change 2007: The Scientific Basis — Contribution of Working Group I to the IPCC 

Fourth Assessment Report,” edited by S. Solomon, D. Qin, M. Manning, Z. Chen, M. 

Marquis, K.B. Averyt, M. Tignor, and H.L. Miller, Cambridge University Press, 

Cambridge, UK, and New York, NY, USA, 2007 

/ISO05a/ “Refrigerant Properties,” ISO standard 17584:2005, International Organization for 

Standardization (ISO), 2005 

/ISO05b/ “Refrigerants — Designation System,” ISO standard 817:2005, International Organization 

for Standardization (ISO), Geneva, Switzerland, 15 January 2005 
46 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

/ISO08/ “Refrigerants — Designation and Safety Classification,” ISO working document ISO/DIS 

817:2008, International Organization for Standardization (ISO), Geneva, Switzerland, 1 

February 2008 

/IUP79/ International Union of Pure and Applied Chemistry (IUPAC), “Nomenclature of Organic 

Chemistry, Sections A, B, C, D, E, F, and H,” prepared by J. Rigaudy and S. P. Klesney, 

Pergamon Press Incorporated, New York, NY, USA, 1979 

/Kaj10/ H. Kajihara et al., “Estimation of environmental concentrations and deposition fluxes of R1234yf and its decomposition products emitted from air conditioning equipment to 

atmosphere,” paper NS24, Proceedings of the 2010 International Symposium on NextGeneration Air Conditioning and Refrigeration Technology, Tokyo, Japan, 17-19 February 

2010 

/Kay10/ Y. Kayukawa, K. Fujii, R. and Akasaka, “Thermodynamic Property Measurements for 

HFO 1234yf and its Binary Mixtures,” Proceedings of the International Symposium on 

Next-Generation Air Conditioning and Refrigeration Technology (Tokyo, Japan), New 

Energy and Industrial Technology Development Organization (NEDO), Kawasaki City, 

Kanagawa Prefecture, Japan, February 2010 

/Kir76/ C. J. Kirwin, “Toxicological Review of Propane, Butane, Isobutane, Pentane, and 

Isopentane,” Phillips Petroleum Company, Bartlesville, OK, USA, November 1976 

/Kna97/ M. Knabe, S. Reinhold, and J. Schenk, “Ammoniakanlagen und Kupfer-Werkstoffe?” 

[Ammonia Systems and Cuprous Materials?], Ki Luft und Kältetechnik, 33(9):394-397, 

1997 

/Kru97/ H. H. Kruse and T. Tiedemann, “Experience with HC Refrigerants and Projections for 

Future Applications,” Refrigerants for the 21st Century (proceedings of the 

ASHRAE/NIST refrigerants conference, Gaithersburg, MD, USA, 6-7 October 1997) 

American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA, 

USA, 44-56, 1997 

/Lec09/ Leck, T. J., “Evaluation of HFO-1234yf as a Potential Replacement for R-134a in 

Refrigeration Applications,” Proceedings of the 3rd IIR Conference on Thermophysical 

Properties and Transfer Processes of Refrigerants (Boulder, CO, USA, June 23-26, 2009), 

International Institute of Refrigeration, Paris France, and the National Institute of 

Standards and Technology (NIST), Boulder, CO, USA, paper 155, June 2009 

/Lem10/ E. W. Lemmon, M. L. Huber, and M. O. McLinden, “NIST Standard Reference Database 

23, NIST Reference Fluid Thermodynamic and Transport Properties –REFPROP” (version 

9.0), Standard Reference Data Program, National Institute of Standards and Technology 

(NIST), Gaithersburg, MD, USA, 2010 

/Leu10/ D. J. Luecken, R. L. Waterland, S. Papasavva, K. N. Taddonio, W. T. Hutzell, J. P. Rugh, 

and S. O. Andersen, “Ozone and TFA Impacts in North America from Degradation of 

2,3,3,3-Tetrafluoropropene (HFO-1234yf), A Potential Greenhouse Gas Replacement,” 

Environmental Science and Technology, 44(1): 44,343–348, 2010 

/Lip97/ H. Lippold, “Kupferwerkstoffe in Ammoniakanlagen” [Cuprous Materials in Ammonia 

Systems], KK Die Kälte- und Klimatechnik, 50(10):730-735, October 1997 

/McL10/ M. O. McLinden, M. Thol, and E. W. Lemmon, “Thermodynamic Properties of trans1,3,3,3-Tetrafluoropropene [R1234ze(E)]: Measurements of Density and Vapor Pressure 

and a Comprehensive Equation of State,” Proceedings of the International Refrigeration 

and Air Conditioning Conference at Purdue, Purdue University, West Lafayette, IN, USA, 

July 2010. 

/NIO76/ “Criteria for a Recommended Standard — Occupational Exposure to Carbon Dioxide,” 

publication 76-194, National Institute of Occupational Safety and Health (NIOSH), U.S. 

Department of Health and Human Services, Cincinnati, OH, USA, August 1976 

/Oha96/ M. M. Ohadi, S. S. Li, R. K. Radermacher, and S. V. Dessiatoun, “Critical Review of 

Available Correlations for Two-Phase Flow Heat Transfer of Ammonia,” International 

Journal of Refrigeration, 19(4):272-284, May 1996 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 47

/PAF95/ “Programme for Alternative Fluorocarbon Toxicity Testing (PAFT) Toxicology 

Summaries,” PAFT, Washington, DC, USA, September 1995 

/PAF96/ “Testing to Extremes — Industry's Cooperative Effort to Test the Health and Safety of 

Selected Fluorocarbon Alternatives to CFCs,” Programme for Alternative Fluorocarbon 

Toxicity Testing (PAFT), Washington, DC, USA, circa 1996 

/Pai91/ C. Pais and R. L. Webb, “Literature Survey of Pool Boiling on Enhanced Surfaces,” 

technical paper 3444 (392-RP), Transactions (Winter Meeting, New York, NY, USA, 19-

23 January 1991), American Society of Heating, Refrigerating, and Air-Conditioning 

Engineers, Atlanta, GA, USA, 97(1):79-89, 1991 

/Pap09/ S. Papasavva, D. J. Luecken, R. L. Waterland, K. N. Taddonio, and S. O. Andersen, 

“Estimated 2017 Refrigerant Emissions of 2,3,3,3-tetrafluoropropene (HFC-1234yf) in the 

United States Resulting from Automobile Air Conditioning,” Environmental Science and 

Technology, 43(24):9252–9259, 2009 

/Pru83/ K. M. Pruett, “Compass Corrosion Guide (Guide to Chemical Resistance of Metals and 

Engineering Plastics),” Compass Publications, La Jolla, CA, USA, 1983 

/Pru94/ K. M. Pruett, “Chemical Resistance Guide for Elastomers II,” Compass Publications, La 

Mesa, CA, USA, 1994 

/Pru95/ K. M. Pruett, “Chemical Resistance Guide for Metals and Alloys,” Compass Publications, 

La Mesa, CA, USA, 1995 

/Ric92/ R. G. Richard and I. R. Shankland, “Flammability of Alternative Refrigerants,” ASHRAE 

Journal, 34(4):20,22-24, April 1992 

/Ric10/ M. Richter, M. O. McLinden, and E. W. Lemmon, “Thermodynamic Properties of 2,3,3,3-

Tetrafluoroprop-1-ene (R1234yf): p-rho-T Measurements and an Equation of State,” 

Journal of Chemical and Engineering Data, in press, 2010 

/San96/ P. Sansalvadore, M. Zgliczynski, and F. Agricola, “Chemical-Physical Aspects in 

Refrigeration with Isobutane,” Applications for Natural Refrigerants (proceedings of the 

IIR Conference — meeting of Commissions B1, B2, E1, and E2, Aarhus, Denmark, 3-6 

September 1996), publication 1996-3, International Institute of Refrigeration (IIR), Paris, 

France, 615-622, 1996 

/Sek00/ A. Sekiya and S. Misaki, “Hydrofluoroethers as Alternatives to CFCs, HCFCs, HFCs, and 

PFCs,” Conference Proceedings of the Earth Technologies Forum (Conference on Climate 

Change and Ozone Protection, Washington, DC, 30 October - 1 November 2000), 

International Climate Change Partnership and the Alliance for Responsible Atmospheric 

Policy, Arlington, VA, USA, 259-265, October 2000 

/Sin95/ A. Singh, M. M. Ohadi, S. Dessiatoun, and W. Chu, “In-Tube Boiling Heat Transfer 

Coefficients of R-123 and their Enhancement Using the EHD Technique,” Journal of 

Enhanced Heat Transfer, 2(3):209-217, 1995 

/Syr90/ Syracuse Research Corporation, “Toxicological Profile for Ammonia,” report TP-90-03, 

Agency for Toxic Substances and Disease Registry (ATSDR), Public Health Service, U.S. 

Department of Health and Human Services, Washington, DC, USA, December 1990 

/Tan09/ K. Tanaka, Y. Higashi, and R. Akasaka, “Measurements of the Isobaric Specific Heat 

Capacity and Density for HFO-1234yf in the Liquid State,” Journal of Chemical and 

Engineering Data, 55(2):901–903, 2010 

/Tan10/ K. Tanaka and Y. Higashi, “Thermodynamic properties of HFO-1234yf (2,3,3,3-

tetrafluoropropene),” International Journal of Refrigeration, 33(3):474-479, May 2010 

/Tho98a/ J. R. Thome, “Boiling and Evaporation of Fluorocarbon and Other Refrigerants: A Stateof-the-Art Review,” Air-Conditioning and Refrigeration Institute, Arlington, VA, USA, 

October 1998 

/Tho98b/ J. R. Thome, “Condensation of Fluorocarbon and Other Refrigerants: A State-of-the-Art 

Review,” Air-Conditioning and Refrigeration Institute, Arlington, VA, USA, October 1998 
48 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

/UNEP06/ “2006 Report of the Refrigeration, Air-Conditioning and Heat Pumps Technical Options 

Committee,” United Nations Environment Programme (UNEP), Nairobi, Kenya, January 

2007 

/UNEP09/ “Handbook for the Montreal Protocol on Substances that Deplete the Ozone Layer (Eighth 

Edition),” United Nations Environment Programme (UNEP), Ozone Secretariat, Nairobi, 

Kenya, 2009 

/UNEP10/ “Technology and Economic Assessment Panel 2010 Progress Report: Assessment of 

HCFCs and Environmentally Sound Alternatives and Scoping Study on Alternatives to 

HCFC Refrigerants under High Ambient Temperature Conditions,” Volume 1 (Decisions 

XXI-9 and XIX-8 Task Force Reports), United Nations Environment Programme (UNEP), 

Ozone Secretariat, Nairobi, Kenya, May 2010 

/Wie09/ M. E. Wieser and M. Berglund for the International Union of Pure and Applied Chemistry 

(IUPAC) Commission on Atomic Weights and Isotopic Abundances, “Atomic Weights of 

the Elements 2007 (IUPAC Technical Report),” Pure and Applied Chemistry, 81(11): 

2131-2156, November 2009 

/WMO10/ “Scientific Assessment of Ozone Depletion: 2010,” report 52, World Meteoro-logical 

Organization (WMO), Global Ozone Research and Monitoring Project, Geneva, 

Switzerland; National Oceanic and Atmospheric Administration (NOAA), Washington, 

DC, USA; National Aeronautics and Space Administration (NASA), Washington, DC, 

USA; United Nations Environment Program (UNEP), Nairobi, Kenya; and the European 

Commission, Research Directorate General, Brussels, Belgium; January 2011 (revised 

printed version in press with expected publication in March 2011) 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 49

Chapter 3 

__________________________________________________________ 

Domestic Refrigeration 

Chapter Lead Author 

Ed McInerney 

Co-Authors 

Martien Janssen 

Paulo Vodianitskaia
50 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

3 Domestic Refrigeration 

3.1 Introduction 

Approximately 100 million domestic refrigerators and freezers are produced annually. Most 

of these are used for food storage in dwellings. Beverage dispensing machines represent a 

small fraction of these total units. Typical storage volumes range from 20 to 850 liters/unit. 

Various fundamental design approaches and consumer convenience features are included 

within the product offerings. A typical product contains a factory-assembled, hermetically 

sealed, vapour-compression refrigeration system employing a 50 to 250 watt induction motor 

and containing 50 to 250 grams of refrigerant. Niche market products in some cases employ 

alternative technologies to vapour-compression refrigeration. The age distribution of the 

global installed products is extremely broad /Wes97/ with median age estimates ranging from 

9 to 19 years at retirement . Long product life and high volume annual production combine 

for an estimated 1500 to 1800 million unit global installed inventory. 

3.2 Options for New Equipment 

HFC-134a or HC-600a (isobutane) continue to be the options for domestic refrigeration new 

production. No new alternatives have matured to become energy-efficient, cost-competitive 

opportunities for these products. New, or original equipment manufacturing production 

conversion from use of ODS alternatives was essentially completed by 2008. The conversion 

trend and refrigerant selection is shown graphically in Figure 3-1. HC-290 usage in blends 

with HC-600a has been included with HC-600s usage in this Figure and data has not been 

normalised to be independent of production volumes. Refrigerant conversion to HC-600a is 

expected to continue, driven by conversion from HFC-134a usage. This is discussed below in 

section 3.2.1.1. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 51

Field service conversion to non-ODS alternatives continues to lag new product conversion. 

This is a consequence of long product life and the absence of drop-in substitutes for the 

refrigerants used in the pre-conversion production units still in service. 

Future product configurations will incorporate evolutionary energy efficiency improvements. 

These will directly influence energy-related emissions. Design approaches for 

environmentally responsible product disposal or recycling at end-of-life retirement is also a 

topic of accelerating interest. 

3.2.1 Refrigerant Options 

As stated above, HFC-134a and HC-600a continue to be the options for domestic refrigeration 

new production. Throughout this chapter, HC-600a discussions include both HC-600a and 

binary blends of HC-600a and HC-290. In situations where capital resources are constrained, 

the use of binary hydrocarbon blends allow matching the volumetric capacity of previously 

used CFC-12 to avoid investments required to modify compressor manufacturing tools. 

These blends result in a small reduction in thermodynamic efficiency versus pure HC-600a 

and could migrate to use of pure HC-600a as capital funds become available. Two industry 

dynamics are of interest: (1) second-generation non-ODS refrigerant usage shift from HFC134a to HC-600a, and (2) preliminary suggestions of low GWP unsaturated fluorocarbons to 

displace HFC-134a usage. Binary hydrocarbon blends can also be used when converting 

from HFC-134a to hydrocarbon refrigerants to match the volumetric capacity of currently 

used compressors and avoid manufacturing investment. 

3.2.1.1 Non-ODS Refrigerant Usage Conversion from HFC-134a to HC-600a 

European production of American style refrigerators began conversion from HFC-134a to 

HC-600a in the early 2000’s. Initial conversions of new production automatic defrost 

refrigerators in Japan from HFC-134a to HC-600a were discussed in the 2006 report of this 

committee /UNEP06/ It is estimated that this conversion, motivated by global warming 

considerations, has progressed to include the majority of new refrigerator production in Japan. 

Recently a major U.S. manufacturer announced its intent to introduce auto-defrost 

refrigerators using HC-600a refrigerant to the U.S. market. This introduction represents a 

significant departure from current North American practices for domestic refrigeration. U.S. 

codes and standards interpretations and modifications required for broad use of HC-600a 

refrigerant are currently in process. Commercial introduction occurred during 2010. 

Concurrently, the number of HC-based refrigerator models offered by manufacturers based in 

countries such as Brazil is rising as well. 

The trend of conversion to hydrocarbon refrigerants will continue in the opinion of the 

authors. Excluding any influence from government regulatory intervention, a ten-yearhorizon estimate is that 75% of new refrigerator production will use HC-600a and 25% will 

use HFC-134a by 2020 /UNEP10/. This estimate is based on the assumptions: 

• All current HC-600a applications will continue. 

• One-half of HFC-134a applications in geographic areas where forced 

convection, auto defrost refrigerators are the typical configuration will convert 

to either HC-600a or a binary hydrocarbon blend having matched volumetric 

capacity to HFC-134a. 

• Three-fourths of HFC-134a applications in geographic areas where natural 

convection and/or manual defrost refrigerators are the typical configuration will 

convert to HC-600a or a binary hydrocarbon blend. 
52 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

• Conversions will be influenced by regional market or climate change policy 

choices. Government regulatory influence was not considered. 

• Substitution will be on an equal-molar basis, i.e. 100 grams of HFC-134a will be 

replaced by 57 grams of HC-600a. 

Technology to accomplish conversions is readily available. The rate and extent of conversion 

will be influenced by premium product cost to maintain product safety with introduction of 

flammable refrigerants. Premium costs are introduced by modified electrical components, 

increased use of reduced voltage to avoid electrical arcing and any specified redundant safety 

devices. Cost pressures will be more significant on model offerings with lower profit margins 

subject to erosion. These will typically be less-featured, lower-end models. 

Conversion of currently installed refrigerators to refrigerants with different characteristics can 

be problematic. Conversion is not recommended without the oversight and endorsement of 

the original manufacturer. 

3.2.1.2 Consideration of Low-GWP Unsaturated Fluorocarbon Refrigerants

Chemical manufacturers developed low atmospheric life unsaturated HFC compounds to 

replace HFC-134a in automotive air conditioning applications. These unsaturated 

fluorocarbons are developmental products and evaluation of their use in stationary 

applications has begun but is not being pursued with high priority. A preliminary, theoretical 

assessment is that HFC-1234yf has the potential for comparable efficiency to HFC-134a in 

domestic refrigerators. Numerous application criteria have not yet been addressed: thermal 

stability, hermetic system chemical compatibilities, process fluid compatibilities, 

contamination sensitivities, etc. Long-term reliability expectations for domestic refrigeration 

use are significantly more demanding than automotive applications. Much new information is 

required before this refrigerant can be established as a viable alternative candidate. However, 

the low GWP and reduced flammability versus HC-600a justify continued attention. 

3.2.2 Not-In-Kind Alternative Technologies

Alternative refrigeration technologies continue to be pursued for applications with unique 

drivers such as very low noise, portability or no access to electrical energy distribution 

network. Technologies of interest include Stirling cycle, absorption and adsorption cycles, 

thermoelectric, magnetic and trans-critical CO2. In the absence of unique drivers such as the 

examples cited above, no identified technology is cost or efficiency competitive with 

conventional vapour-compression technology for mass-produced domestic refrigeration 

equipment. Absorption refrigeration equipment has been used in hotel mini-bar units due to 

low noise levels and for mobile, off-network applications such as campers or mobile homes 

for many years. Thermoelectric or Stirling cycle technologies are used for portable 

refrigerated chests in applications such as medical transport. Equipment for trans-critical CO2

use of Stirling cycle technology is developed and available for limited quantity usage in 

applications such as packaged beverage vending machines. This technology is not considered 

a logical candidate for domestic refrigeration because of very small compressor swept volume 

requirements, reduced thermal efficiency and higher system cost versus current practice 

/Bee08/. Magnetic refrigeration is considered a conceptual development topic and is 

premature for consideration as a viable alternative. The remaining specialty niche product 

areas cited above would each require high capital investment to establish mass production 

capability. These product technologies will not be further discussed in this report focused on 

options for mass produced markets. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 53

3.2.3 Product Energy Efficiency Improvement Technologies 

The energy efficiency of domestic refrigeration products is a topic of accelerating consumer 

and regulatory interest. Relative energy efficiency provides direct linkage to relative energyrelated global warming of refrigeration technology options via power consumed during the 

product useful life. A more extended discussion of efficiency improvement options was 

included in the 2002 report of this committee /UNE02/. Additional comments are contained 

in reports under the Eco-Design Directive studies /Eco06/. These studies provided capability 

background used for updating European minimum energy efficiency standards /EU09/. 

Significant technology options to improve product energy efficiency have already 

demonstrated mass production feasibility and robust, long-term reliability. Both mandatory 

and voluntary energy efficiency regulation programs catalysed industry product efficiency 

development efforts. Various energy test procedures have the intent to predict consumer 

energy consumption. Though standardisation activities aiming at a universal test protocol are 

in progress /IEC59M/, currently each test procedure is unique and the results from one should 

never be directly compared to results from another. A number of improved energy efficiency 

design options are fully mature, and future improvements of these options are expected to be 

evolutionary. Examples of these options include efficient compressors, high efficiency heat 

exchangers, improved low thermal loss cabinet structures and gaskets, and less variable 

manufacturing processes. Extension of these to all global domestic refrigeration would yield 

significant benefit, but is generally constrained by availability of capital funds. Similarly, 

retooling compressor manufacturing facilities would allow recovery of the minor efficiency 

penalties incurred with the use of HC-600a/HC290 blends versus pure HC-600a. 

Design options with less economic justification are sometimes introduced in premium-cost 

models having incentive subsidies. This provides the opportunity to mature new efficiency 

technologies and progress them through their individual cost/experience curves. This 

increases the likelihood for migration of the efficiency technologies to more cost-sensitive 

model line segments. Options that presently have limited or newly introduced application 

include variable speed compressors; intelligent controls; system reconfigurations, such as dual 

evaporators; advanced insulation systems; and Demand Side Management (DSM) initiatives 

requiring interactive communication with energy providers. The premium-cost of these 

options currently restrict their application to high-end models and constrain their proliferation 

for general use. 

• Variable capacity compressors avoid cycle losses and inertial losses through 

modulating capacity and compressor speed. Use of higher efficiency permanent 

magnet or linear motors is also enabled by electronic commutation controls. 

• Intelligent, adaptive controls allow variable control algorithms that avoid optimising 

at seldom-experienced worst-case conditions. 

• Parallel dual evaporators can improve Carnot theoretical efficiency by effectively 

reducing required pressure ratios of the higher temperature evaporator. Cost–

effective, reliable and stable system controls need to be demonstrated. 

• Advanced vacuum panel insulation concepts have been selectively used for several 

years in Japan, Western Europe and the United States. Their premium cost has 

constrained extension to general use. 

• Power line load management initiatives reduce energy service provider peak load 

demands. Early embodiments created intermittent loss of product function and 

resulted in consumer dissatisfaction. More recent developments provide utilitytriggered feature constraint or capacity reduction of the product. 
54 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

3.3 Options for Existing Equipment

Service conversion to non-ODS refrigerants has significantly lagged original equipment 

conversion. The distributed, individual proprietor character of the service industry resists coordinated efforts to convert from ODS refrigerants. Field service procedures typically use 

originally specified refrigerants. Refrigerant blends developed specifically for use as drop-in 

service alternatives have had limited success. Their acceptance has been good in regions with 

mandatory service regulations promoting their use. Blend selection appears to be more 

related to provider distribution strength than technical performance. The interested reader is 

referred to the 1998 report of this committee for an extended discussion of field repair and 

conversion options /UNEP98/. Chapter 2 in this current report contains an updated listing of 

refrigerant blend options. 

Non Article 5 countries completed conversions of new equipment production to non-ODS 

substances approximately 15 years ago. The final production ODS-containing products are 

now approaching the end of their life cycle, transitioning this to a sunset issue in these 

countries. In Article 5 countries, service demand for ODS refrigerants is expected to remain 

strong for more than ten-years as a result of their later conversion to non-ODS refrigerants. 

Limited capital resources also favour rebuilding service options in Article 5 countries versus 

replacement by new equipment. This further delays installation of new production units 

employing non-ODS refrigerants. Rebuilding has the accompanying consequence of voiding 

the opportunity to significantly improve product energy efficiency and reduce stress on the 

power distribution grid. Unless there is governmental intervention, service refrigerant 

demand for CFC-12 is expected to continue for legacy products. 

3.3.1 Drop-In Conversion of In-Service Products 

Drop-in conversion of existing in-service units to alternative refrigerants has been limited. 

Consumer safety consideration requires that any potential for flammable fluid accumulation 

within an enclosed volume must avoid the potential within that volume for an electrical spark, 

electrical arc or surface temperature above the auto-ignition temperature of the leaked gas in 

air. The extent of in-service product modification to assure this is dependent upon the original 

product configuration. The original equipment manufacturer is most familiar with the product 

construction and should be consulted for required modifications prior to decision to proceed. 

• Cold-wall-evaporator constructions require leaking refrigerant to diffuse through the 

refrigerator inner liner or flow by convection through apertures in the liner in order 

to accumulate within the cooled volume. There is a very low probability of 

significant gas accumulation. Additionally, electrical components located within the 

cooled volume are limited and consequently there is a low probability of an ignition 

source within the enclosed volume. Economical drop-in conversion of this 

configuration is alleged to be viable by some spokesmen, but procedure definition 

by the original manufacturer should be sought prior to decision to proceed 

• Thin-wall evaporators positioned within the cooled volume are a common 

construction for automatic-defrost refrigerators. Leakage of refrigerant can 

accumulate within the cooled volume and the risk of ignition is dependent on 

whether the rate of leakage is sufficient to result in a combustible mixture within the 

cooled volume. Additionally, electrical components are commonly located within 

the cooled volume -- thermostats, convective fans, radiant defrost heaters, lights, 

icemakers, etc. – providing an elevated probability of an ignition source being 

present. The viability of a drop-in conversion will depend upon the extent of 

original construction modification required to achieve an acceptable configuration. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 55

Again, conversion procedure definition by the original manufacturer is prudent and 

should be sought prior to decision to proceed. 

3.4 End-of-Life Conservation and Containment Concerns 

Domestic refrigerators typically contain 50 to 250 grams of refrigerant. The small unit 

charge and the geographically dispersed location of these units complicate commercial 

opportunities to promote recovery and recycling initiatives to manage emissions from 

disposed units. Mandatory end-of-life refrigerant handling regulations have existed in many 

countries for several years. Chapter 11 of this report addresses this and related conservation 

approaches. 

3.5 Current Refrigerant Use 

Domestic refrigeration annual refrigerant demand data are not reported but can be estimated 

using reasonable assumptions. Data required are historic annual unit production quantities, 

original equipment specified refrigerant and charge quantity information. Annual refrigerant 

demand for new equipment production has been calculated using this information and is 

summarised in Table 3-1. Field service refrigerant demand estimates are significantly less 

certain and have not been included for that reason. 

3.5.1 New Equipment Production 

The conversion of domestic refrigeration original equipment manufacture to non-ODS 

refrigerants is summarised in Table 3-1. Transition to non-ODS refrigerants in original 

equipment manufacture is essentially complete. Sixty-three percent of current production 

uses HFC-134a refrigerant, 36% uses either HC-600a or an HC-600a/HC-290 blend and 1% 

uses other refrigerants, primarily HCFC-22 or HFC-152a. 
56 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 3-1 Estimated 1992 to 2008 Production of Domestic Refrigerators and Freezers by Refrigerant Type

Global Region Year New Unit Production,Units New Unit Refrigerant Use, Tonnes

CFC12 HFC134a HC600a1 Other2 Total CFC12 HFC134a HC600a1 Other2 TOTAL

Weatern Europe 1992 16.3 16.3 2280 2280

1996 11.2 6.1 17.3 1220 410 1630

2000 8.2 11.3 19.5 890 760 1650

2004 3.5 16.4 19.9 380 1080 1480

2008 3.6 19.2 22.8 390 1260 1650

Eastern Europe 1992 7.5 7.5 1500 1500

1996 2.8 3.2 6.0 320 370 690

2000 0.7 2.1 0.3 0.1 3.2 140 260 30 20 450

2004 1.7 2.6 4.3 210 210 420

2008 3.3 5.0 8.3 410 400 810

North America 1992 11.6 11.6 1750 1750

1996 12.5 12.5 2290 2290

2000 13.6 13.6 2420 2420

2004 17.1 17.1 3150 3150

2008 16.1 16.1 2970 2970

Central & South America 1992 4.0 4.0 600 600

1996 8.2 8.2 1280 1280

2000 1.4 6.1 7.5 230 1360 1590

2004 8.4 8.4 1850 1850

2008 12.6 12.6 2640 140 2780

Asia & Oceania 1992 18.7 0.5 19.2 3160 80 3240

1996 14.0 9.5 0.2 1.6 25.1 2270 1520 20 200 4010

2000 9.7 9.2 4.4 1.2 24.5 1570 1470 440 150 3630

2004 2.2 15.7 8.3 1.5 27.7 360 2530 830 190 3910

2008 25.9 12.9 1.5 40.3 4170 1290 190 5650

Africa & Mid-East 1992 5.2 5.2 840 840

1996 3.4 0.7 4.1 590 120 710

2000 2.8 0.9 3.7 490 150 640

2004 0.8 3.8 4.6 140 640 780

2008 4.3 4.3 880 880

World Totals 1992 63.3 0.5 63.8 10130 80 10210

1996 28.4 37.1 6.3 1.6 73.4 4460 5520 430 200 10610

2000 14.6 40.1 16.0 1.3 72.0 2450 6550 1230 170 10400

2004 3.0 50.2 27.3 1.5 82.0 500 8760 2120 190 11570

2008 65.8 37.1 1.5 104.4 11460 3090 190 14740

Footnotes: 1 Includes HC-600a + HC-290 blends 2 HCFC-22 and HFC-152a 

3.5.2 Field Service

Data are not available to reasonably predict global refrigerant demand for field service. First 

order estimates with assumed service rates from industry service sources suggest 3 to 5 

kilotonnes total annual demand. Approximately one-half of this demand is estimated to be 

ODS refrigerant to service legacy products in the field. The remaining demand is expected to 

be for non-ODS refrigerants used to service products manufactured following new equipment 

production conversions. New product refrigerant service demand will be proportional to the 

various new product refrigerant demands. 

As mentioned above, transition from ODS refrigerants in non-Article 5 countries was 

completed over 15 years ago. ODS service refrigerant demand in these countries is 

significantly reduced since the elapsed time following the conversion is comparable to the 

typical product life span. The limited residual ODS refrigerant service demand is served with 

recovered and recycled original charge refrigerant. Service blends are used where adequate 

recycled ODS refrigerant supply is not available or regulations preclude the use of ODS. The 

remaining majority of service demand is for non-ODS refrigerants to service products 

produced after the transition from ODS refrigerants. This demand is served with newly 

manufactured refrigerant. 

Conversion of new equipment production to non-ODS refrigerants in Article 5 countries 

occurred over a span of two to fifteen years ago. This later conversion extends the service 

transition issue in these countries. Service refrigerant demand is expected to continue to be 

for originally specified refrigerants: CFC-12 for legacy product and either HFC-134a or HC600a and HC-290 for new production. CFC-12 demand for product service will continue to be 

strong for another decade and then diminish over the subsequent decade. ODS refrigerants 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 57

will continue to be used while they are available and economic. The dispersed and 

uncoordinated nature of the service industry limits opportunities to develop an effective 

recovery and recycling supply stream. Mandatory service regulations could promote use of 

drop-in replacement refrigerants and reduce emissions of ODS refrigerants. 

3.5.3 Future Refrigerant Demand Implications

Refrigerant demand for domestic refrigeration use is expected to continue to grow slowly, 

driven by product saturation increase in Article 5 countries and the growing number of global 

dwelling units. Two factors are anticipated to alter refrigerant selection and influence relative 

demands plus there is always the remote possibility for new developments to modify demand 

in a discontinuous manner. 

Second generation non-ODS refrigerant migration from HFC-134a to HC-600a in new 

product production is occurring as a result of the GWP difference between the two 

alternatives. This migration began in Japan several years ago and was recently introduced on 

a limited basis in the United States. No new technology is required and the trend will likely 

proliferate. The rate and extent of proliferation will be influenced by the relative cost for 

HFC-134a and HFC-600a products. Current estimates indicate premium cost results from 

design changes to allow the use of flammable refrigerants in automatic defrost refrigerators. 

This suggests that voluntary migration across all product lines is not likely in countries with 

high litigation frequency. 

Second generation conversion from HC-600a/HC-290 blends to pure HC-600a could result 

from desires for improved product energy efficiency. No new technology would be required. 

Efficiency differences are small and controversial. Economic or energy efficiency drivers 

alone may not be sufficient to justify this conversion. Charging method simplification and 

compressor component standardisation for hydrocarbon usage are added benefit opportunities. 

The integrated implications of historic refrigerant demand are summarised in the refrigerant 

bank discussion in the Annex of this report /Pal03, Clo06, CEP09/. The 2006 update of these 

data continue to demonstrate domestic refrigeration bank growth. The data indicate an 11% 

typical 3-year growth rate for the bank in Article 5 countries and a 3% typical 3-year growth 

rate in non-Article 5 countries. The aggregate domestic refrigerant bank in 2006 was 

estimated to be 153,000 tonnes: 40% CFC-12, 54% HFC-134a and 6% HC-600a. 

Approximately 53%of the bank resides in Article 5 countries and 47% resides in non-Article 

5 countries. The composition of the bank reflects growth of HFC and HC refrigerants and 

decline of CFC refrigerants, consistent with substitution of non-ODS refrigerants for CFCs. 

An estimated 71% of residual CFCs in the bank reside in Article 5 countries. 

3.5.4 Future Refrigerant Emission Implications 

The 2006 aggregate domestic refrigeration emissions, including end of life emissions, were 

estimated to be 9619 tonnes, or 6.8% of the total domestic refrigerant bank. Emissions were 

77% CFC-12, 21% HFC-134a and 2% HC-600a. Since transition from use of CFC-12 in new 

production is complete, nearly all of the CFC emissions originate from the existing bank of 

legacy refrigerators. Geographic distribution of these emissions will be biased toward Article 

5 countries since they hold the majority of the bank /CEP09/, have higher equipment repair 

rates /UNEP98/ and longer product lifetimes /CEP09/. 
58 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

The emissions trend to non-ODS alternatives from the refrigerant bank is heavily damped. 

This sluggish response results from the 1500 to 1800 million unit installed base and long 

product life. Refrigerant systems are hermetically sealed during manufacture; and the majority 

of these units never require sealed system service. This intrinsic reliability results in 

emissions being dominated by end-of-life disposition. This suggests management of CFC-12 

potential emissions from legacy refrigerators may be the largest domestic refrigeration 

opportunity for emission avoidance.

3.6 References 

/Bee08/ M. van Beek and M. Janssen, “R-744 compared to R-290 in small freezer applications,” 8th

IIR Gustav Lorentzen Conference on National Working Fluids, Copenhagen, 2008. 

/CEP09/ Domestic refrigeration refrigerant bank updated data through 2006. Authors, CEP, Ecole 

des Mines, December 2009. 

/Eur01/ Euromonitor International Inc. “Global Appliance Information System,” February 2009, 

http://www.euromonitor.com. 

/Eco06/ Eco-design requirements of EuP. Domestic Refrigerator and Freezer Directive Studies, 

July 2006, http://www.ecocold-domestic.org. 

/EU09/ European Commission regulation (IEC) No. 643/2009 of 22 July 2009 implementing 

Directive 2005/32/EC of the European Parliament and of the Council with regard to 

ecodesign requirements for household refrigerating appliances. 

/IEC59M/ “Performance of electrical household and similar cooling and freezing appliances.” 

/SAE08/ SAE CRP1234, “Industry Evaluation of Low Global Warming Potential Refrigerant 

HFO1234yf,” (December 2008). 

/Tur07/ 2nd International Workshop on Mobile Air Conditioning and Auxiliary Systems, Torino, 

Italy, “HFO-1234yf: A Low GWP Refrigerant for MAC,” (November 2007). 

/UNEP98/ UNEP 1998 Report of the Refrigeration, Air Conditioning and Heat Pumps Technical 

Options Committee, Chapter 3, Domestic Refrigeration (1998 Assessment). 

/UNEP02/ UNEP 2002 Report of the Refrigeration, Air Conditioning and Heat Pumps Technical 

Options Committee, Chapter 3, Domestic Refrigeration (2002 Assessment). 

UNEP06/ UNEP 2006 Report of the Refrigeration, Air Conditioning and Heat Pumps Technical 

Options Committee, Chapter 3, Domestic Refrigeration (2006 Assessment). 

/UNEP10/ UNEP Technology and Economic Assessment Panel Task Force Decision XXI/9 Report, 

“Assessment of HCFC’s and Environmentally Sound Alternatives Paragraph 2C,” (May 

2010). 

/Wes97/ Roy W. Weston Inc., Recycling Rate Determinant Study – Phase 1 Report, Norcross, 

Georgia (1997).
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 59

Chapter 4 

__________________________________________________________ 

Commercial Refrigeration 

Chapter Lead Author 

Denis Clodic 

Co-Authors 

Michael Kauffeld 

Peter Nekså 

Per-Henrik Pedersen 

Roberto Peixoto 
60 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

4 Commercial Refrigeration 

4.1 Introduction 

Commercial refrigeration is characterised by storing and displaying food and beverages at 

different levels of temperature within retail environments. The refrigerating capacities of 

equipment vary from some hundred Watts to 1.5 MW. Refrigerant choices are depending on 

the two main levels of temperatures necessary for the conservation of fresh food and 

beverages on one hand, and frozen food on the other hand. The more compact the equipment, 

the better the refrigerant containment. Centralised systems used in large supermarkets are the 

most emissive due to the large number of joints, expansion valves, and the possible failures 

due to oil return, corrosion, and vibrations. HCFC-22 represents still the largest refrigerant 

bank in commercial refrigeration and is used at all temperature levels. . Research and field 

tests have been carried out aiming at defining new technical options in order to use 

refrigerants with zero ODP and low GWP, to keep at least the same energy efficiency for the 

new systems, to improve their leak tightness, and to lower the refrigerant charges. 

4.2 Application 

4.2.1 Equipment and Systems 

Commercial refrigeration is composed of three main categories of equipment: stand-alone 

equipment, condensing units, and supermarket systems. 

Stand-alone equipment consists of systems where all refrigeration components are integrated 

and, for the smallest types, the refrigeration circuit is entirely brazed or welded. Stand-alone 

equipment, including freezers, vending machines, and beverage coolers, are extensively used 

in many Article 5 countries. 

For developing countries, domestic refrigerating equipment, refrigerators and freezers can be 

found in small shops and are used for commercial purposes. Stand-alone equipment emits its 

refrigerant charge mainly at end of life when decommissioning, if no stringent recovery 

policy is in place and enforced. 

Condensing units exhibit refrigerating capacities ranging typically from 1 kW to 20 kW, they 

are composed of one (or two) compressor(s), one condenser, and one receiver assembled into 

a so-called “condensing unit”, which is located external to the sales area. The cooling 

equipment consists of one or more display case(s) in the sales area and/or a small cold room. 

Condensing units are typically installed in specialty shops such as bakeries, butcher shops, 

and convenience stores. In a number of small supermarkets, one can find a large number of 

condensing units (typically up to 20) installed side-by-side in a small machinery room. In 

most of the A5 countries, the use of systems employing condensing units is very extensive. 

Annual emission rates are estimated between 7 and 12%. 

Centralised systems are the preferred option in supermarkets. They operate with racks of 

compressors installed in a machinery room (see figure 4-1). A number of possible designs 

exist. Two main design options are used: direct and indirect systems. 

Direct systems are the most widespread. The refrigerant circulates from the machinery room 

to the sales area, where it evaporates in display-case heat exchangers, and then returns in 

vapour phase to the suction headers of the compressor racks. The supermarket cold rooms are 

cooled similarly. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 61

Figure 4-1: Multiple compressor racks in machinery rooms for medium and low 

temperature display-cases / Clo08/ 

In the machinery room, racks of multiple compressors are installed with common suction and 

discharge lines, and each rack is usually associated with an air-cooled condenser. Specific 

racks are dedicated to low temperature and others to medium temperature. Each refrigerant 

circuit of each rack is independent. Supermarket centralised systems with long piping circuits 

have led to large refrigerant charges (100 to 3,000 kg depending on the size of the 

supermarket) and consequently led to large losses when ruptures occur. Some commercial 

companies have studied /Ets07/ and taken measures in order to limit refrigerant leaks; their 

report show how they reduce emissions from 25% annual emission level to about 12%. So 

the typical emission rates of small supermarkets vary between 15 and 25% and those of large 

supermarkets between 20 and 35%. These figures represent, in general, the non-Article 5 

situation. The emission rates for most of the Article 5 countries are much higher. 

Figure 4-2: Indirect system with MPG (Mono-propylene-glycol) at the medium 

temperature level and R-744 at the low temperature level / Clo08/ 

Indirect systems (see Figure 4-2) are composed of primary heat exchangers where a heat 

transfer fluid - HTF (also called secondary refrigerant) - is cooled and pumped to the display 

cases where it absorbs heat, and then comes back to the primary heat exchanger. HTFs have 

received much interest in recent years because indirect systems allow for a lower primary 

refrigerant charge and facilitate the use of flammable or toxic refrigerants when isolated from 

the sales area /Rhi09/. Other designs including the so-called distributed systems and hybrid 

systems have been developed (see section 4.5.3). 
62 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

4.2.2 Data on Outlets and stand-alone equipment 

Commercial refrigeration encompasses equipment installed in hotels, bars, restaurants, gas 

stations, train platforms, speciality shops (butchers, fishmongers, deli shops...), convenience 

stores and supermarkets. The sizes of the stores depend on opening hours, social habits, road 

infrastructure, and type of habitat. In 2006, the number of supermarkets world-wide is 

estimated at 280,000 covering a wide span of sales areas varying from 400 m2

 to 20,000 m2

(among them 10,000 very large supermarkets with food sales areas varying between 2,000 

and 5,000 m2

). 

Note: Available data are coming from marketing studies where the type of outlets is defined in 

different ways depending on the study. The data imply uncertainties on the level of refrigerating 

equipment especially in fast developing countries. 

World-wide in 2006, the number of mini-markets is estimated at 4 million where condensing 

units are mostly used. Condensing units are also used in many other stores; their number is 

estimated at 34 million units. 

The number of food retail stores is estimated at 9.8 million where stand-alone equipment and 

even domestic refrigerators and freezers are found. In 2006, the population of vending 

machines and other stand-alone equipment is evaluated at 20.5 and 32 million units, 

respectively. 

Based on those data, the refrigerant bank in 2006 was estimated at 340,000 MT and was 

distributed as follows: 

 46% in centralised systems; 

 47% in condensing units, and 

 7% in stand-alone equipment. 

The estimated sharing of refrigerants per type is about 15% CFCs, which are still in use in 

Article 5 countries, 62% HCFCs the dominant refrigerant bank and still for many years, and 

23% HFCs that have been introduced in new equipment in Europe and Japan as of 2000 . 

Note: In 2006, HCs mainly introduced in standalone equipment are not visible in terms of 

refrigerant bank. 

4.3 Options for New Equipment 

Complementary to information on refrigerant choices, issues on energy conservation and 

energy efficiency will be briefly addressed in order to underline possible advantages and 

drawbacks of refrigerant choices on energy efficiency. 

4.3.1 Stand-Alone Equipment 

The main families of stand-alone equipment are vending machines, ice makers, ice cream 

freezers, water fountains, and plug-in display cases. 

Part of stand-alone equipment such as wine-coolers, professional kitchen refrigerators and 

freezers, and hotel mini-bars, is based on the same technology as domestic refrigerators and 

freezers. Consequently the technical options of these series of equipment are analysed in 

Chapter 3, and similar trend of replacement of HFC-134a by hydrocarbons (HC-) is observed 

but for standalone equipment HC-290 is the refrigerant of choice rather than HC-600a. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 63

Other types of stand-alone equipment have a specific design: water coolers, ice makers, 

vending machines, and display cases, and are covering also several levels of temperatures. 

For food and beverages kept at temperatures ranging from +1 °C up to 10 °C, HFC-134a is 

the dominant refrigerant, replaced by HC-600a and HC-290 in some families of equipment 

where generally the refrigerant charge is small lower than 150 g for most manufacturers even 

if some European brands commercialise equipment with Hydrocarbon charge up to 1 kg and 

even 2.5 kg depending on national regulation. For other companies R-744 is the preferred 

refrigerant choice. 

Ice Cream freezers 

For ice cream freezers, R-404A as well as HFC-134a has been the standard design since 1995; 

the switch from HFC refrigerant to propane (HC-290) is steady. The lifetime of the 

equipment is about 10 years, The estimated installed base using HC is of 500,000. 

Water Fountains 

Water fountains for both bottled water and tap water are installed in office buildings, 

supermarkets, etc. They are installed with a small compressor refrigeration system and so far 

HFC-134a is the most used refrigerant. Typical HFC-134a charge is about 40 g. Some 

companies are now introducing HC-600a with refrigerant charge as low as 20 g and the 

market share of those HC systems is growing. 25% of the installed base in 2010 is estimated 

to be using HC-600a taking into account a life time of 10 years and knowing the current 

policies of the large global companies. 

Ice Machines 

A large number of ice machines are installed in restaurants, bars, and hotels. Several sizes are 

available and refrigeration capacities vary from 1 to 10 kW, with refrigerant charge varying 

accordingly from some hundred grams to 1 kg. Company policies as well as country 

regulations will lead to different refrigerant choices: HFC-134a, hydrocarbons and possibly 

R-744. So far, HFC-134a is globally the dominant choice. 

Vending Machines 

The cooling capacity of vending machines is about 600 W for rapid cooling of cans. HFC134a is the standard refrigerant in vending machines. One global company has chosen R-744 

as a refrigerant. This new R-744 system is installed inside a plug-in/pull-out cassette and its 

energy efficiency, as measured, is as good as the reference HFC systems up to 32°C ambient 

temperature. One global company has taken the commitment that all new equipment will be 

HFC free as of 2015. Several others are following the same path. R600a appliances have also 

been developed, but its application is limited to certain styles of construction.R-744 and HC 

vending machines are taking a significant market share in Japan. One OEM has developed a 

not-in-kind Stirling refrigeration prototype for vending machines. The energy efficiency of 

this new system was better than the reference vapour compression base line, but the cost was 

considered too high by customer companies and so this system did not reach the market. 

Glass-Door Coolers 

Glass-door bottle coolers can be found in supermarkets, convenience stores, gas stations etc. 

The most common type is the one-door 400-litre-type. Glass-door coolers are often installed 

by a soft drink company. 
64 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Currently, HFC-134a is the standard choice. Since 2000, several thousand units have been 

installed in Europe using mostly HC-600a and, for some brand names, HC-290. Some global 

companies have rather chosen R-744 systems for their bottle coolers. 

Plug-in Display Cabinets 

The use of plug-in display cabinets is increasing in small and medium size supermarkets. 

This choice is made because plug-in cabinets are cheaper and more flexible than remote 

display cabinets connected to a centralised system. In warm climate countries and in general 

during the hot season, the heat released by the condenser of each and every plug-in cabinet in 

the sales area has to be removed by an air-conditioning system, which has to be designed with 

a significant larger cooling capacity. On the other hand, in colder climates such as Northern 

Europe, the heat rejected by the condenser and compressor is useful in heating the store and 

can be regarded as heat recovery in the cold season. So far, R-404A refrigerant is the standard 

choice, and the charge per unit varies from 220 g up to 3 kg. Especially in Germany, UK and 

the Northern European countries plug-in display cabinets running on HC-290 are gaining 

market share. Several German supermarket chains only purchase HC plug in cabinets /Rhi09/. 

There has been conversion of production facilities from HCFC and HFC to HC for standalone commercial refrigeration equipment in Article 5 countries for the domestic market 

/GTZ09i/. 

In many Article 5 countries, even in large supermarkets, plug-in cabinets are preferred to 

remote cabinets connected to a centralised system. The evident drawback is that plug-in 

cabinets are releasing all heat inside the sales area and either the AC system has to be 

designed in order to absorb this additional heat load or the temperature inside the supermarket 

can reach very high values (above 30 °C and sometimes above 40 °C) leading to a poor 

capability of plug-in cabinets to keep the products at the right temperature. Moreover, the 

overall energy efficiency of supermarkets using plug-in cabinets is low due to the fact that the 

energy efficiency of small motor-compressors is lower than medium and large size 

compressors. 

For all stand-alone equipment, energy conservation standards can be and are being issued or 

revisited because laboratory tests can be performed in order to assess refrigerating capacities 

and electric input power, and so establishing equipment energy efficiency. The base line 

energy consumption can be established, engineering analyses can be performed, and 

improvements can be targeted. Regulations as well as electricity costs are the drivers for 

significant improvements of energy efficiency, the market being driven by initial costs so far. 

It is estimated that all refrigerants banked in stand-alone equipment represent an amount of 

about 38,000 tonnes, emission levels during the lifetime is estimated from 1 to 5 % depending 

on servicing quality, corrosion and day to day handling of goods . Due to the compact 

refrigeration circuit, leaks at the beginning of the life cycle of the equipment are well handled; 

the number of joints being minimal or even nil (all brazed or welded circuit). The critical 

issues are related to corrosion, equipment day-to-day handling, and aggressive cleaning 

leading to possible circuit ruptures. Emissions occur essentially at end of life 

decommissioning. 

In summary, HFC-134a fulfils the technical constraints in terms of reliability and energy 

performance for stand-alone equipment. In many developed countries GWP of HFC-134a is 

more and more considered as prohibitive in relation to refrigerant emissions, so HC 

refrigerants and R-744 are gaining significant market shares in Europe and Japan. In the near 

future, unsaturated HFC such as HFC-1234yf could be considered as an option, the retrofit 

from HFC-134a to this new refrigerant expected as being rather simple even if long-term 

reliability has to be assessed /See 10/. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 65

4.3.2 Condensing Unit Systems 

Condensing units are found in many convenience stores and food specialist stores for cooling 

a small cold room and one or several display cases. The technology can be considered as a 

mass production one with usually hermetic compressors, sometimes semi-hermetic ones. 

Condensing unit is a well spread option in Article 5 countries. Even in supermarkets, 

especially in some Article 5 countries, several racks of condensing units are installed side-byside in small machinery rooms. Condensing units are less energy efficient, compared to a 

well-designed small-centralised system but condensing units are chosen for initial cost 

reasons, easiness of installation, and are found ready to install. 

The cooling capacity varies from 1 to 20 kW mostly at medium temperature and the 

refrigerant charge varies from 1 to 5 kg for HCFCs or HFCs. HCFC-22 is still the most used 

refrigerant in the U.S. and in all Article 5 countries. New equipment can use HFC-134a, 

HCFC-22, R-404A, R-407C, R-507, R-410A other HFC and HCFC blends, HC refrigerants 

and R-744. HFC-134a, HCFC-22 and R-404A are the dominant refrigerants. In Europe, due 

to the E.U. regulation, a shift from HCFC-22 to R-404A or sometimes R-507A has occurred 

as of 2000. R-404A is the leading choice also for cost reasons; the condensing units using 

this refrigerant are cheaper compared to HFC-134a units of the same cooling capacity because 

of smaller compressor. Nevertheless in hot climate and for medium temperature applications, 

HFC-134a is used due to its better energy performances at high ambient temperatures 

compared to R-404A. 

Condensing units are always designed as direct expansion systems, and so their 

environmental impacts are related to refrigerant choice and energy efficiency. 

What is described for stand-alone equipment is also verified for condensing units when the 

units are replacing larger compressors. As stated previously, this non-efficient solution in 

terms of energy consumption is chosen due to investment cost reasons and to the availability 

of condensing units everywhere in the world. Moreover, these condensing units are also 

produced in large series in Article 5 countries avoiding the import of large size compressors. 

4.3.3 Supermarket Systems 

Centralised systems 

For large supermarkets, the dominant design is the so-called centralised system where all the 

compressor racks are installed in a single machinery room. This concept has led to the 

installation of up to several kilometres of piping, containing refrigerant in liquid phase from 

the machinery room to the sales area and refrigerant in vapour phase back from the sales area 

to the machinery room. The size of centralised systems can vary from refrigerating capacities 

of about 20 kW to more than 1 MW related to the size of the supermarket. 

The refrigerating capacities are generated by independent racks of compressors at two main 

levels of evaporating temperatures -40 / -35°C for frozen food (and ice-creams) and -15 / -

10°C for fresh food (dairy, meat etc.). Low-temperature racks represent about 10 to 30% of 

the refrigerating capacities and so the medium-temperature racks represent 70 to 90% of the 

total refrigerating capacities. In terms of energy consumption, the low-temperature racks 

consume 20 to 35% of the total energy consumption due to lower energy efficiency related to 

the level of temperature. The refrigerant charges are related to the refrigerating capacity and 

store layout. For large supermarkets (food sales area larger than 3,000 m2

) with current direct 

expansion centralised systems, the refrigerant charge varies from 800 kg to 2 tonnes. 
66 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Heat recovery for heating the store typically requires a 4-way valve on each condensing 

circuit and also dedicated heat exchangers in order to recover the condensation capacity 

during the heating season; this energy is usually released to the environment by the air cooled 

condensers. This possible design is popular in cold regions in the USA and in some European 

countries, . The circuit is more complicated, the refrigerant charge is higher by at least 20%. 

This technical option has to be studied in terms of return on investment, level of refrigerant 

emissions and servicing. For moderate and hot climates this option is not selected due to the 

added complexity and the low heating needs that hamper the return on investment. Other 

simpler designs are found in Europe, especially in the northern countries where domestic hot 

water is produced by de-superheating the refrigerant before entering the condenser. A new 

system design mostly introduced in small supermarkets integrates the cooling / heating system 

of the shop with the refrigeration system, making an interesting example of a holistic 

approach for energy management. 

In order to simplify servicing in the current centralised design, most of the commercial 

companies, except in Japan, has chosen to use the same refrigerant at the two levels of 

temperatures. This choice is arguable because as an example HFC-134a or R-407C and R717 are more efficient as refrigerants at the medium-temperature level compared to R-404A 

and on the contrary R-404A or R-744 are the most efficient refrigerants at the lowtemperature level. As always the design of the system defines the effective energy efficiency 

and so efficient design can be found even with a less efficient refrigerant. Nevertheless, in 

terms of choice of refrigerant, one can keep in mind that refrigerants could be different for the 

medium-temperature level and for the low-temperature level giving a larger number of 

technical options when environmental impacts of refrigerants have to be limited. 

One of the major consequences of making separate choices for refrigerants dedicated to the 

low-temperature and to the medium-temperature is that R-744 can be the preferred choice at 

the low-temperature level in a cascade design and the choice for the medium-temperature 

level is under evaluation in developed countries depending on global warming, costs, and 

easiness of use. In parallel to refrigerant evaluation, technical options have been developing 

since nearly 15 years in order to lower the refrigerant charge by the development of indirect 

systems and distributed systems. 

Distributed Systems 

This technical alternative has been studied and realised as of 2000. The concept is to install 

the compressors close to the display cases either inside or very close to the sales area. 

Figure 4-3: Distributed system where a single package refrigerating system provides 

refrigeration to a series of display cases / Clo08/ 

This design is more practical for the typical US layout of supermarkets where most of the 

medium-temperature display cases are installed near by the walls and not in aisles, as it is 

usual in Europe. The reference design of distributed system integrates water condensers in a 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 67

soundproof box with the compressor(s). The water, used as a coolant in the condensers, is 

cooled usually by roof-mounted dry coolers. The refrigerant charge can be reduced by more 

than 50% and up to 75%. While at the same time leakage rates are reduced due to fewer 

joints. 

The energy efficiency of such a system has to be carefully analysed. Energy gains can be 

made due to the huge reduction of piping length and thereby reduced pressure losses, but the 

compressors are smaller and so their energy efficiencies are usually lower. Moreover, an 

additional difference of temperature is created when using water-cooled condensers that are 

releasing their heat in air-dry coolers. The complexity of the comparison between the baseline 

(centralised system) and the new distributed system is enhanced when changing the 

refrigerant (HFCs, HCs, or R-744 compared to R-22); so a wide variation of performances 

can be found in the technical literature. Distributed systems are still not a widespread option 

and are mainly installed in new US supermarkets with HFC refrigerants. 

It has to be noted that indirect-distributed systems have been developed in UK. The system 

uses hydrocarbon as a refrigerant and a heat transfer fluid for transferring heat from the 

display cases to the evaporator. 

Indirect Systems 

Indirect systems represent a small market share of new installations and they replace direct 

expansion centralised systems in supermarkets. This option has been developed in Europe as 

of 1995 and has expanded initially slowly. It has to be noticed that several US commercial 

chains have decided since 2006 to install indirect systems. The driver to change from usual 

direct expansion systems is the significant reduction of refrigerant charges (50 to 85 %) and a 

much better refrigerant containment. 

Depending on the country, R-404A or R-507, sometimes R-717, HCs (HC-290 or HC-1270), 

and R-744 are used as primary refrigerants in the refrigerating system entirely installed in the 

machinery room. Due to high latent heat of vaporisation and low liquid density, the ammonia 

(R-717) charge can be 10% of the usual HFC refrigerant charge. Such systems can be 

installed in special machinery rooms with safety features allowing high ventilation rates in 

case of significant leaks. 

The same applies to HC refrigerants with charge typically 10% of the direct system HFC 

reference charge. For safety reasons, the refrigerant circuits are separated in several 

independent ones, limiting the refrigerant charge of each system /IPCC05/. 

Many indirect systems have been designed, still using R-404A as primary refrigerant in the 

machinery room, the reduction of the charge yields to significant reduction of the 

environmental impact. 

Well-designed indirect systems can be as efficient as well-designed direct systems due to 

better heat exchange in the air coils, but heat transfer fluids (HTF) such as mono-propyleneglycol (MPG) used in indirect systems need special attention, especially at low temperatures 

where pumping power may be excessive. Alternative HTFs exist which have lower viscosity 

at low temperatures. Nonetheless, indirect systems are nowadays mainly built for the Medium 

Temperature range. Also the pumps have to be carefully chosen in order to avoid significant 

additional energy consumption. 

For indirect systems, R-744 as HTF is mainly used in low-temperature display cases and cold 

rooms. R-744 is partially evaporated in the display-case evaporators, returns in two-phase 

flow to the primary evaporator in the machinery room, where R-744 is fully condensed or 

“liquefied”, and then pumped back to the display cases. Such design is energy efficient 
68 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

because there is no superheat zone at the exit of each evaporator. The only threat for indirect 

systems using R-744 is the possible release of the entire R-744 charge related to a lack of 

cooling due to an incident on the refrigerating system. The R-744 pressure increases 

progressively with the lack of cooling and is related to the temperature in the circuit. If the 

safety valve is set around 3 MPa (which is usual), the opening of the safety valve will occur 

when the temperature of the coldest part of the system is about – 5 °C leading to a release of 

R-744. 

More generally, indirect systems are linking all cooling elements one to the others, which in 

case of a significant failure leads to the complete loss of refrigeration and the possible loss of 

food. The current multiple-rack centralised system offers the possibility of limiting the 

incident on a single rack, the other ones being capable to provide the complementary cooling 

during the repair. Special charge limitation rules have led to a similar design for indirect 

systems in Sweden. Namely racks of individual refrigeration systems, all cooling the same 

indirect loop. Up to 20 such racks are installed in large Swedish supermarkets. One German 

discount chain has announced that they will only purchase indirect hydrocarbon systems for 

their new supermarkets. 

A drawback of indirect systems is related to the necessary insulation of all piping in order to 

avoid humidity condensation and icing. Valves and pumps can present difficulties for 

efficient insulation and may become ice blocks with water dripping continuously around the 

ice blocks; moreover, for liquid HTF used at the medium-temperature level, quantities are 

enormous representing several metric tonnes, and possible leaks of HTF are difficult to 

diagnose especially in the display cases. All those lessons learnt from the existing indirect 

systems are to be tackled by improved designs. 

Hybrid and Cascading Systems 

Hybridisation between direct and indirect systems can be found in the current technical 

offerings (one example is shown in figure 4-4) with a limited additional cost if any. 

Figure 4-4: Hybrid system comprising a R-744 cascade at the low temperature level and a 

secondary system at the medium temperature level / Clo08/ 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 69

R-744 is no more a HTF but a refrigerant used in a cascade system. The overall design 

consists in a low-temperature compressor rack with R-744 compressors working between an 

evaporating pressure of 1.2 MPa (evaporating temperature around –35°C) and a condensing 

pressure of 2.5 MPa (condensing temperature at –12°C) possibly 3 MPa (condensing 

temperature at –5.5 °C), and so keeping the tubing and the components under the 2.5 or 3 

MPa pressure threshold, which are the thresholds of current technologies. The consequence is 

that the costs are kept similar between R-744 and HFC systems. For larger stores (above 2500 

m2

 sales area) the use of R-744 in cascade system is even more cost effective due to smaller 

pipe dimensions. 

In a hybrid system, the condensation of the R-744 low-temperature stage is made by either 

exchanging heat with the heat transfer fluid used at the medium-temperature stage or by the 

evaporation of the medium temperature refrigerant in an evaporator – condenser as shown in 

figure 4-4, so that the heat of the R-744 system is delivered at the medium-temperature stage 

and then released outdoor by the medium-temperature vapour compression system. This 

concept has been installed in very large supermarkets and is claimed to meet the same initial 

costs as R-404A direct systems, because the R-404A charge is reduced from 1.5 tonne to less 

than 250 kg. This design is in competition with full cascading systems presented in the 

following section. 

Such systems are starting to be used in some Article 5 countries, for example see /GTZ09ii/. 

Another variation is the use of a high temperature HTF circuit which is fed to water-cooled 

condensing units positioned within medium and low temperature display cases and next to 

cold stores. This enables the minimisation of refrigerant charge within the retail area (figure 

4-5), thereby allowing the use of HCs. At least one supermarket chain is now using this 

approach /ACR09/. 

Two stage R-744 booster systems 

The most up-to-date design of R-744 refrigeration system employs R-744 both for the low 

temperature and the medium temperature range. One common design is the one described in 

Fig 4-1, another is that the compressors for the low temperature stage are cascaded with those 

of the medium temperature stage, figure 4-5. This design is becoming popular in Central and 

Northern Europe where it exhibits lower energy consumption on a yearly basis compared to 

usual centralised systems. For high outdoor temperatures, R-744 is no longer condensed in the 

outdoor air cooled condenser due to R-744 low critical temperature of 32 °C. The energy 

efficiency can be lower than that of a comparable R404A system during this transcritical 

operation. This is the reason why such systems have only been installed in moderate climates. 

One German discount chain has announced that it will only purchase R-744 refrigeration 

systems from January 2010 on and various UK supermarkets have given similar such 

commitments /Kau07/. 

Figure 4-5: All-R-744 centralised refrigeration system /Rhi09/. 
70 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Current Centralised systems 

HCFC-22 is now being phased-out in new installations in all developed countries, Europe 

having begun as of 2000. HCFC-22 represents still the largest refrigerant bank in 

supermarkets and hypermarkets in the U.S., in Russia, and in almost all A5 countries. For 

new systems, the dominant choice is R-404A for all non-Article 5 countries except some 

Northern European countries. For example in Norway and Denmark, due to the high level of 

taxes on R-404A, nearly all new centralised systems (40 to 70 each year) are working with R744 at the low and the medium level temperatures. In addition, Denmark has prohibited the 

use of HFC in systems with more than 10 kg refrigerant charge. Consequently many non-HFC 

systems are being built. In UK and Germany even without high taxes on high GWP 

refrigerants, R-404A is no longer the preferred choice. 

In Japan, R-407C is the leading choice for medium-temperature applications, which is the 

dominant use of commercial refrigeration due to the large consumption of fresh and raw food. 

R-404A is used for all low-temperature applications. 

In China HCFC-22 and HFC-134a, to a lesser extent, are the most used refrigerants with R404A being used for HCFC-22 replacement in many low-temperature systems. 

HCFC-22 is still a dominant option for all Article 5 countries because the cost of HCFC-22 

technology is the cheapest and compressors are available on the global or local market. 

Under hot climates, R-404A exhibits lower energy efficiency compared to HCFC-22 due to 

its lower critical temperature (72 °C) compared to HCFC-22 (86.5 °C). 

Additional sub-cooling of R-404A is a cost and energy efficient strategy that can be 

performed by a small independent cooling system for cooling only the R-404A liquid phase 

leaving the condenser. 

In moderate climates of Central and Northern Europe direct systems with R-744 as refrigerant 

in a trans-critical / sub-critical cycle depending on the ambient temperature, have been 

introduced in several countries for medium and large size supermarkets. The systems give a 

low GWP refrigerant solution with only one refrigerant for both low and medium-temperature 

refrigeration. About 300 systems have been installed in Europe during the past years. A 

complementary option is a cascade system where R-744 is the refrigerant of the lowtemperature circuit; as shown previously for the hybrid system (Figure 4-4). This design is 

more efficient than a full R-744 cascade system in hot climates, and is being considered for 

application in some Article 5 countries. However, all-R-744 systems with slightly modified 

cycle design in order to increase efficiency at the highest ambient temperatures are now being 

field-tested. 

In summary, for supermarkets with refrigerating capacities varying from less than 100 kW to 

at least 1 MW, several designs have been experimented in several hundreds of stores. The 

main specifications of commercial chains are to keep the design simple, easy to maintain and 

service, and capable to avoid the loss of food products when a failure occurs on the 

refrigerating systems. Those specifications have to be compatible with refrigerant charge 

reduction and choice of refrigerants with 0 ODP, lower GWP, and energy efficiency 

improvements. 

4.5 Options for Existing Equipment 

CFCs (CFC-12 and R-502) have been phased-out in new commercial refrigeration equipment 

in most Article 5 countries as of 2005; there is still a need for servicing commercial 

refrigerating systems running with those CFCs during the next years. So far, no shortage of 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 71

recycled CFCs has been identified, confirming the same evaluation as noticed ten years before 

in developed countries. Intermediate HFC-blends such as R-413A are used for retrofit of 

CFC-12 medium-temperature systems, and R-417A or R-422B for retrofit of R-502; those 

retrofits have not taken a significant market share of refrigerant sales. 

Retrofit of commercial refrigeration equipment raises a larger interest in Article 5 countries to 

save cost. In order to make reliable retrofit, a significant training of servicing technicians is 

necessary even if technical solutions are well established. For many servicing companies, the 

knowledge as well as the equipment is not always available. Retrofits require the change of 

lubricant and need more technical precautions. The availability of the new POE lubricants as 

well as the new filter dryers has to be verified. In Article 5 countries, for many servicing 

companies still a significant lack of adequate tooling is obvious: recovery equipment, 

connecting hoses, recovery cylinders, dry vacuum pump, and precise scale. All those tools 

and equipment are necessary to realise proper retrofit including the main steps: recovery, 

evacuation, oil flushing, change of oil, and careful charge of the new refrigerant, all those 

elements are part of training programs currently implemented in Article 5 countries. 

For HCFCs, the status of use varies widely depending on regulations. In Europe, the use of 

virgin HCFC-22 for servicing purposes ceases as of 1st January 2010; only recycled HCFCs 

can be used until 1st January 2015. 

In the US, HCFC-22 production and import cease as of 1st January 2010 for new refrigerating 

equipment; servicing is authorised until 2020, but HCFC quantities are limited. For 

developed countries several studies indicate the need of strong conversion programs of 

existing commercial refrigerating systems due to possible shortages of HCFC-22 for 

servicing. As it will be shown in the following paragraph, several options are proposed. 

Stand-Alone Equipment and Condensing Units 

Three known options are available depending on projected remaining lifetime and costs: 

- Disposal of the old equipment and buy a new one using a non-ODS refrigerant, 

- Repair and recharge with the same refrigerant, and 

- Repair and recharge with a low-ODP or zero-ODP refrigerant. 

Conversions of stand-alone equipment and condensing units moving from CFC-12 to HFC134a are well established. The conversion from HCFC-22 to HFC blends is now ongoing in 

developed countries. It has to be underlined that for all brazed stand-alone equipment 

equipped with a capillary tube and having an all brazed refrigerating circuit, conversion is 

unlikely. The possible retrofit concerns mostly condensing units and involves several steps. 

Chemical manufacturers propose several HFC blends. The choice depends on the level of 

temperature and is the same for condensing units and large centralised systems. 

The change from alkyl-benzene oil to POE lubricant is recommended, the adjustment of the 

superheat in case of thermostatic expansion valve, and the replacement of the filter dryer. 

These procedures have been well established since several years, but continuous training is 

still necessary in many Article 5 countries to ensure retrofit quality and so the remaining 

lifetime of the retrofitted equipment. 

Supermarket Systems 

In developed countries, supermarket equipment is partially or totally renewed every 7 to 10 

years, depending on countries. In Article 5 countries, the lifetime is significantly longer, 15 

years up to 25 years, so the retrofit options have a very significant impact in order to limit 

costs to avoid the change of the refrigerating system. 
72 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

R-502 Retrofit 

Due to lubricants issues, R-502 retrofits are mainly carried out with HCFC-22-based blends 

(R-408A or R-402B). Studies performed on energy consumption show that energy efficiency 

obtained with these blends is comparable with R-502. Neither major problems nor 

breakdowns have been recorded. It appears to be a straightforward and reliable option. 

HCFC-22 Retrofit 

New HFC blends such as R-422D and R427A, have been developed in order to make easy 

retrofit from HCFC-22 to those HFC blends. R-422D is presented as a blend where no oil 

change is necessary due to the 3.4% of HC-600a mixed with 65.1% of HFC-125 and 31.5% of 

HFCF-134a. Different tests have shown that depending on the circuit, a progressive change 

of the previous alky-benzene oil by POE leads to a better oil return to the compressor racks. 

R-427A is presented as refrigerant blend for HCFC-22 replacement with an initial change of 

oil. Retrofit has begun in Europe and in the U.S. but has not gained a significant momentum 

until now. Moreover, the price of HCFC-22 remained low until 2008 not indicating any 

immediate shortage; only in 2009 did HCFC-22 prices raise but not in all developed 

countries. 

For energy efficiency, the change from R-22 to those retrofit blends indicates a loss in 

refrigerating capacities varying from 5 to 10% and a loss in energy efficiency in the same 

order of magnitude. For such large systems it may be unnecessary to adopt such alternative 

intermediate blends and instead directly apply R-407C, especially since it has a lower GWP 

compared to those two blends and that the oil change required for the use of this refrigerant is 

a better servicing practice. 

4.9 References 

/ACR09/ HFCs reduced as Waitrose shelves CO2 for a greener future, ACR News, UK, October 

2009. 

/Ass06/ Assawamartbunlue, K., Brandemuehl, M. J., Refrigerant Leakage Detection and Diagnosis 

for a Distributed Refrigeration System, HVAC Research, Vol. 12, No. 3, July 2006. 

/Bax03b/ Baxter, V.D. (éd.), 2003b: Advanced supermarket refrigeration/Heat recovery systems. 

Vol. 2, Country Reports. IEA Heat Pump Center, 73 pp (CD-ROM ISBN: 90-73741-49-1). 

/Bir00/ Birndt, R., Riedel R. and Schenk J., 2000 Tightness of Commercial Refrigeration Systems, 

Research Project Commissioned by the Forschungsrat Kältetechnik 

/Bir00/ Birndt, R., Riedel R. and Schenk J., 2000: Dichtheitvon Gewerbekälteanlagen (Tightness 

of commercial refrigeration systems. Die Kälte – und Klimatechnik, 9/2000, 56-63 (in 

German). 

/Biv04/ Bivens, D. and Gage, C., 2004: Commercial refrigeration systems emissions. In the 

proceedings of the 15th Annual Earth Technology Forum, April 204, Washington, USA. 

/Clo08/ Clodic D. Saba S., Slim R., Palandre L. Inventory of Direct and Indirect GHG Emissions 

from Stationary Air Conditioning and Refrigeration Sources, with Special Emphasis on 

Retail Food Refrigeration and Unitary Air Conditioning CARB Agreement No. 06-325 –

December 2008 

/Clo06/ Clodic, D., Palandre, L., Barrault, S., and Zoughaib, A., 2006: Short report of Inventories 

of the worldwide fleets of refrigerating and air conditioning equipment in order to 

determine refrigerant emissions. The 1990 to 2003 updating. ADEME final report. 

/DOE09/ DOE - Energy Conservation Program: Energy Conservation Standards for Refrigerated 

Bottled or Canned Beverage Vending Machines; Proposed Rule, 10 CFR Part 431, Federal 

Register / Vol. 74, No. 102 / Friday, May 29, 2009. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 73

/Est07/ Estberg, E. R., Supermarket Refrigerant Leaks – Perspective, February 9, 2007 

/EU00/ Regulation (EC) no. 2037/2000 the European Parliament and of the Council of 29 June 

2000 on substances that deplete the ozone layer. 

/Gir04/ Girotto, S., Minetto, S. and Nekså, P., (2004): Commercial Refrigeration with R-744 as 

Refrigerant, Experimental Results, Int. J of Refrigeration, Vol 27 (7), November 2004 

/GTZ09i/ Converting the Production of Refrigeration Equipment to Natural Refrigerants, Deutsche 

Gesellschaft für Technische Zusammenarbeit (GTZ), 2009 

/GTZ09ii/ Conversion of Supermarket Refrigeration Systems from F-Gases to Natural Refrigerants, 

Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ), 2009 

/Haa05/ Haaf, S., Heinbokel, B. and Gernemann, A. 2005: Erste CO2-Kälteanlage für Normal- und 

Tiefkühlung in einem Schwezer Hypermarket, Die Kälte & Klimatechnik, 2/2005 

/IPCC05/ IPCC, 2005: Safeguarding the ozone layer and the global climate system. Issues related to 

Hydrofluorocarbons and Perfluorocarbons. Cambridge University Press. 2005. ISBN: 13-

978-0-521-68206-0. 

/Kau07/ Kauffeld, M., Trends and Perspectives in Supermarket Refrigeration, EU conference to 

focus on R744 refrigeration, Germany, 2007 

/Kaz06/ Kazachki, G. S., Hinde, D. K., Secondary coolant systems for supermarkets, Ashrae 

Journal, September 2006. 

/Rhi09/ Rhiemeier, J.-M.; Harnisch, J.; Kauffeld, M.; Leisewitz, A.: Comparative Assessment of 

the Climate Relevance of Supermarket Refrigeration Systems and Equipment. 

Environmental Research of the Federal Ministry Of The Environment, Nature 

Conservation And Nuclear Safety Research Report 206 44 300, UBA-FB 001180/e, March 

2009 

/Saw06/ Sawalha, S., Suleymani, A., Rogstam, J., Project 2: CO2 in Supermarket Refrigeration, 

Project report, Phase 1, 2006. 

/See10/ Seeton Ch., Wilson D., Countdown to R-1234yf industry preparation, SAEScottsdale 

symposium July 2010. 

/UNEP05/ UNEP, 2005: Multilateral Fund for the Implementation of the Montreal Protocol. Policies, 

procedures, guidelines and criteria. UNEP 2005. 

/UNEP03/ UNEP, 2002 Refrigeration, AC and Heat Pumps Assessment Report, ISBN XXXX, UNEP 

Nairobi, March 2003 

/WDI04/ World Data International on line, The World Bank Group, 2004. 

2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 75

Chapter 5 

__________________________________________________________ 

Industrial Refrigeration 

Chapter Lead Author 

Andy Pearson 

Co-Authors 

Holger König 

Alexander C. Pachai 

Contributor 

Guangming Chen
76 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

5 Industrial systems

5.1 Introduction 

Industrial systems are characterised primarily by the size of the equipment (physical size and 

heat transfer capability) and the temperature range covered by the sector. Previous RTOC 

reports have concentrated on Industrial Refrigeration: cooling systems for production, storage 

or distribution of food, drink, chemicals, pharmaceuticals and other products. This report will 

extend the discussion on Industrial Heat Pumps: heating systems similar in scale and 

application to Industrial Refrigeration systems and will introduce a new sector called 

Industrial Air-Conditioning. This sector includes systems for controlling air temperature in 

production factories, computer centres and other process areas. In addition to size of 

installation the distinguishing traits of Industrial Air-Conditioning systems are that the 

cooling is not purely for human comfort, the load is not primarily seasonal and the operation 

of the facility would be jeopardised by failure of the cooling equipment. Such systems are 

sometimes called “Mission Critical” and have special design requirements, including the need 

for uninterrupted service, which are not typically provided by traditional HVAC practices 

/ASH09/. Large chillers used for air cooling in offices, hotels, convention centres and similar 

installations are not covered by this chapter. Detailed information on those systems will be 

found in chapter 9 on chillers. A brief overview of the use of HFCs in Rankine cycle 

electrical generation is also given. 

Industrial Refrigeration systems are characterised by heat extraction rates in the range 10kW 

to 10MW, typically at evaporating temperatures from –50o

C to +20oC. There is some overlap 

at the lower end of the capacity scale with commercial refrigeration for shops, restaurants and 

institutions: industrial systems in this sub-sector are characterised by the complexity of the 

design and the nature of the installation. The size of the industrial refrigeration market is 

difficult to assess because it covers such a broad range of applications. Some useful insights 

can be gained from consideration of the market for evaporative condensers, as they are used 

for heat rejection in the majority of large installations. Data for 2009 was analysed for three 

global regions; Europe / Russia, North America and India / China. It is assumed that the 

value of the condenser accounts for 5% of the selling price of the refrigeration system – 

analysis of a wide range of projects showed that the value of the condenser was in the range 

3% - 7% of the total refrigeration contract value. 

Table 5-1: Estimated market value (2009) for large Industrial Refrigeration installations 

 Total Condenser 

Sales (US$M) 

Estimated Total 

Market (US$M) 

Proportion of R-717 use 

Europe/Russia 42 830 90% 

North America 77 1,500 95% 

India/China 45 900 90% 

Evaporative condenser manufacturers also report that 90% of the condensers sold in Europe, 

Russia, India and China are for R-717 systems. In North America the proportion is even 

higher, at 95%. The balance are used on HCFC-22, R-404A, R-507A or occasionally HFC134a. The results are shown in table 5-1. 

Smaller industrial systems more often use air-cooled condensers, and in these cases the 

refrigerant is more likely to be a fluorocarbon, although air-cooled condensers with stainless 

steel tubes are used in smaller R-717 systems. Typically if HCFC-22 is still permitted, for 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 77

example in Article 5 countries, it will be used for these smaller systems. If ozone depleting 

substances have already been prohibited then the likely refrigerants will be R-404A and R507A for low temperature systems and HFC-134a for high temperature systems. Experience 

of accelerated ODS phase out in Europe showed that HCFC-22 systems continue to be 

deployed right up to the phase-out deadline. The same pattern of behaviour has been 

observed in the United States in recent years where HCFC-22 has just been prohibited. Table 

5-2 shows the estimated value of the refrigeration market for the same regions with the split 

between R-717, HCFC-22 and HFCs. It should be noted however that there may be 

significant variations within the regions from country to country or state to state due to 

legislation or tradition. For example the use of R-717 in small industrial systems is quite 

common in Germany, but not in France, and is virtually unknown in Canada and some states 

in the USA, such as New Jersey. It is also noted that the prohibition of HCFC-22 in the USA 

from 1 January 2010 will cause a rapid shift to either R-717 or HFCs, but it is not clear which 

will be preferred. 

Table 5-2: Estimated 2008 market value for small Industrial Refrigeration installations 

 Estimated Total 

Market (US$M) 

Proportion of R717 use Proportion of 

HCFC-22 use 

Proportion of 

HFC use 

Europe/Russia 200 25% 10% 65% 

North America 300 10% 80% 10% 

India/China 500 5% 90% 5% 

For Article 5 countries still using HCFC-22 and looking to the future it is possible that a 

different pattern will emerge. Fear of the consequences of a possible “phase-down” of HFCs 

might result in a switch directly from HCFC-22 to R-717 for new systems. In many ways this 

is simpler than switching to HFCs and then to R-717 at a later date. For example the 

traditional lubricants used with HCFC-22 can also be used with R-717, whereas alternatives 

(typically polyol ester) are required for HFCs and are not compatible with R-717. 

Industrial Heat Pump systems have heat delivery rates from 100kW to over 100MW, with the 

heat source usually at ambient temperature or the waste heat temperature of an industrial 

process. These systems are usually required to deliver higher temperatures than domestic or 

commercial heat pumps used for space or water heating as described in chapters 8 and 9. 

Typical temperatures are in the range 60 oC to 80 oC, although if the recovered heat is to be 

used for steam raising then it needs to be at least 120 oC. Heat recovered from large industrial 

systems is usually transferred to water or a heat transfer fluid and used for process heating or 

for supply to district heating systems. Direct heating of air from large systems is unusual 

because of the large volume of air that would be involved. 

There is no single component of the system that can be identified and tracked to give an 

indication of the overall market size, because the compressors could equally be used in other 

industrial systems and the condenser will be a bespoke design suited to the heating application 

– most probably a fluid heater such as a plate and frame heat exchanger or shell and tube 

pressure vessel. The market is probably around 5% of the industrial refrigeration market in 

Europe, and less in North America, India and China. 

Industrial Air-Conditioning systems cannot be differentiated from commercial systems on 

size alone, as many commercial office buildings have large cooling loads. An industrial 

system requires a higher level of reliability and is subject to year-round high loads. These 

systems may provide human comfort in highly populated areas with large heat loads, for 
78 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

example in trader rooms or dealer floors with a lot of computing equipment. Other Industrial 

Air-Conditioning systems are primarily required to maintain acceptable processing conditions 

for equipment such as computer servers in data centres. In some cases the mission-critical 

part of a total cooling load may be supplied in conjunction with a comfort cooling system, 

configured so that, in the event of partial failure of the system, the mission-critical cooling is 

maintained at the expense of the comfort of the occupants of the rest of the building. Often 

the chillers used for Industrial Air-Conditioning are the same type as described in Chapter 9 – 

the market information and options for future change are described there. However many 

other industrial systems are custom designed for the application. 

An assessment of the relative importance of the traditional HCFC and HFC alternatives in the 

three main market segments of the industrial sector is shown in Table 5-3 /UNE10/. Where 

blends containing HCFCs are shown, for example in the case of R-403B, these are refrigerant 

formulations developed as substitutes for CFCs, in particular R-502. Blends shown as HFCs, 

for example R-404A, were developed as CFC replacements too, but have also been used in 

new build and retrofit applications as replacements for HCFCs. 

Each of the three sub-sectors described in the table is broken down in a more detailed review 

in section 5.2 where sub-sub-sectors such as cold storage, leisure and process are identified 

and analysed. 

Table 5-3: Assessment of alternatives in the Industrial Sector 

A further use of HFCs not covered elsewhere in this report is in a closed evaporation and 

condensation cycle for the generation of electrical power (or other useful work) from the 

expansion of high pressure gas. The basic system, called the Rankine cycle, is similar to the 

process used for power generation in steam turbines, but operates at lower temperatures 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 79

(dependent on the working fluid properties) and so can make use of heat from geothermal 

sources or rejected from industrial processes. When HFCs are used as the working fluid these 

systems are called Organic Rankine Cycles (ORC) /Zyh03/. The Rankine cycle uses heat to 

evaporate the working fluid at relatively high pressure. The resultant gas is passed through an 

expansion engine which does useful work, usually driving an alternator to produce electrical 

power. The low pressure gas at the expander outlet is condensed, usually by rejecting heat to 

atmosphere in a cooling tower, and the resultant liquid is pumped up to evaporating pressure 

by a liquid pump. The conversion rate from thermal to electrical power varies with the 

pressure differences and the expansion engine efficiency, but typically is between 10% and 

15%, including the electrical power required to drive fans and pumps in the system /Les09/. 

Some ORC systems use HFC-134a as the working fluid. It has the advantage of being 

relatively cheap and available, but has a low critical temperature and so cannot take full 

advantage of higher temperature heat sources. Other systems use HFC-245fa or HFC-236fa, 

which have significantly higher critical temperatures. The GWP of HFC-245fa is 

approximately 1000, whereas for HFC-236fa it is approximately 9300, so it is likely that 

future commercial systems will be based on HFC-245fa unless severe restrictions are placed 

on all high GWP HFCs. A fluorinated ketone (CF3CF2C(O)CF(CF3)2, also known as C6F) 

has been used as an alternative. It has zero ODP and zero GWP but less favourable properties 

than HFC-245fa /Bra08/. Rankine cycles have also been produced using R-717 and ammoniawater mixtures as the working fluid, although strictly speaking these cannot be described as 

“Organic”. The relatively high investment cost and relatively low rate of return mean that 

these systems are generally limited to use in large process plants, although a few systems have 

been installed in commercial buildings. 

Thirty years ago chlorofluorocarbons were widely used in the industrial sector in many 

European countries, particularly blends, such as R-502. The particular advantage of these 

substances was their low index of compression which permitted single stage operation over a 

wider pressure ratio than could be achieved with R-717 or even HCFC-22. Other countries, 

notably the United States and Canada had not moved away from R-717 to the same extent as 

some European countries. In the heat pump sector CFC-12, which has a critical temperature 

of 112 o

C, was common for small to medium sized applications and R-717 was used in larger 

systems. Industrial Air-Conditioning was less common at that time, and tended to use 

standard chillers with CFC refrigerant. The move away from CFCs in the late 1980s 

prompted by the Montreal Protocol presented particular problems in the industrial sector 

because the replacement fluids with lower or no ozone depleting potential were not as suitable 

over the wide operating range required. In some places this resulted in a swift return to R-717 

technology, for example in the United Kingdom /Bro92/. In other countries the re-adoption 

of R-717 was more widely resisted and the adoption of low ODP refrigerants was coupled 

with widespread use of secondary refrigerant systems. Other parts of the world followed 

similar patterns, for example R-502 had been common in Japan. The industrial sector there 

responded to its removal by the development of compact, low charge R-717 systems and the 

use of secondary systems with a limited charge of the more expensive HFC fluids. In Article 

5 countries where R-717 was already used these systems were retained and extended, but the 

designs used tended to be old-fashioned and not as efficient or safe as the new Japanese or 

European innovations. In countries with no history of R-717 use, or with no support 

infrastructure the solution was often to use large numbers of smaller light commercial systems 

to satisfy a large cooling load. This is not only expensive to install and maintain, it is also 

much less efficient in operation. 

With increased emphasis on climate change in recent years the importance of energy 

efficiency is now far greater than before. This has led to a reappraisal of previous policies, 

for example in the growing trend for central systems with R-717 rather than multiple 

commercial systems with HCFCs. There is also a greater focus on system integration to make 

better use of waste heat recovery. 
80 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

In Europe regulation on the use of fluorinated gases has also encouraged users to consider R717 and other developments such as the use of R-744 in cascade systems. The motivation 

seems to be primarily based on the fear of as-yet unknown future regulation rather than the 

immediate effect of the current rules, which are mainly aimed at commercial and mobile airconditioning. In the industrial sector it is likely that the adoption of R-717 and R-744 by 

users who previously deployed HCFC-22 and HFC blends will reduce the energy-related 

global warming potential through increased efficiency as well as eliminating the direct global 

warming potential caused by refrigerant leakage. 

To date there has not been any significant discussion of sustainable manufacture of industrial 

systems. It is left to producers to minimise material content on cost grounds rather than for 

environmental reasons, however this can lead to acceptance of lower efficiency systems in 

some cases. For example the design temperature difference used for selection of air-cooled 

condensers is in the range 15 – 20 K, resulting in relatively cheap, small heat exchangers. It 

is possible to get improved efficiency by using larger heat exchangers but they use more raw 

material and are more expensive. There is no clear guidance on optimising this design 

decision, for example information on the embodied energy in the heat exchanger, or preferred 

source of materials. The use of recycled aluminium in heat exchangers is one example of 

sustainable manufacture. Design for minimising steel or copper content is another. In future 

it is expected that greater use of plastics and other synthetic materials will raise awareness of 

sustainable manufacture. 

5.2 Applications (including size of market, current practice, regional 

variations) 

5.2.1 Food Processing 

Refrigeration is used for chilling and freezing food during processing, in order to prolong 

shelf life, but it can also be used to make handling or processing easier. For example hams 

are temporarily frozen to enable them to be sliced more thinly. Chilling also plays a part in 

the pasteurising process where the product is rapidly cooled after heat treatment to minimise 

spoilage. A wide variety of chilling and freezing techniques are used, including immersion in 

liquid, air blast freezing in batches or in a continuous process and contact freezing on tables 

or in blocks between metal plates. The choice of process depends on the form that the 

product takes, whether it is wrapped or unwrapped, robust or fragile, processed or raw. Some 

fruits and vegetables such as potatoes, apples and most soft fruit are notoriously difficult to 

freeze as the expansion of water destroys the cell walls, leading to mushiness when thawed. 

Other produce, such as peas, corn and beans, can be frozen in very small pieces using a 

fluidised bed of air to allow each individual piece to freeze without agglomerating. 

A technique developed in Japan offers the prospect of successful freezing of difficult products 

such as milk and soft fruit, using a magnetic field to condition the product during the freezing 

process /Suz05/. This may help to overcome the negative public perception of frozen food, 

which is that thawed food will always be inferior quality to fresh. In fact if good quality food 

is frozen professionally immediately after harvest, catch or cooking it should offer increased 

shelflife and superior quality when thawed. Spoilage rates could be substantially reduced if a 

greater proportion of food were frozen before shipment. If the public perception of frozen 

food is improved then there could be a significant increase in this sector of the market. 

5.2.2 Cold Storage 

Cold storage facilities usually operate at two temperature levels. Frozen produce must be 

stored below -18o

C, and it is usual to maintain the store between -22oC and -26oC to provide a 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 81

factor of safety in the event of major equipment failure. Some products require lower 

temperatures. Ice-cream and similar produce is stored between -26o

C and -29oC, and some 

niche market products such as some types of sushi must be kept significantly colder, even 

down to -60o

C, in order to retain product quality. Chilled produce is typically held between 

0o

C and 4oC, although fruit, bakery products and vegetables are stored between 8oC and 12oC. 

Some stores offer long term storage contracts, in order to stock produce until it is “out of 

season” and therefore more valuable. Stock may be held for months in these warehouses. 

Other sites provide marshalling facilities in order to restock supermarkets on a daily basis; in 

these plants the product is not usually in the building for more than 24 hours. The cooling 

load on such a building is high because of the amount of traffic through the temperature 

controlled chambers, although product load is typically low because the residence time is not 

long enough for the air temperature to have any appreciable effect on the product. 

5.2.3 Industrial Cooling in Buildings and IT Centres 

Some production processes require tight control of the surrounding temperature, for example 

microchip production, paint spraying or injection moulding. These loads are relatively 

constant all year, and production output is affected if the chilling plant is inoperative, so both 

the reliability and the efficiency of the equipment are more important than for office air 

conditioning. This can sometimes lead to the specification of uniquely designed siteconstructed systems to deliver the cooling in order to provide the high level of reliability 

required, or to achieve lower energy use. Where heat loads are too high to be handled by airor water-based cooling systems, for example in some high density data centres and other IT 

cooling applications, other fluids including R-744 have been used in direct systems /Hut05/. 

Typical loads for these applications may be up to 2kW per m2

 in comparison to a typical 

office load of 40W per m2

. 

The industrial cooling load is typically almost entirely “sensible” cooling – reducing the air 

temperature without reducing the moisture content, in contrast with a typical commercial air 

conditioning load which is likely to involve more dehumidification, or “latent” cooling. 

Latent cooling requires lower temperatures to bring the air to its dewpoint. If an industrial 

cooling load is 100% sensible cooling, or if the cooling can be split into separate systems for 

sensible and latent cooling, then the operating temperature for the sensible cooling can be 

raised, making the system more efficient. 

5.2.4 Industrial Heat Pumps and Heat Recovery 

Many industrial processes including brewing, dairies, food factories and chemical processes 

require large amounts of heat in addition to a cooling load. Even if the primary use of heat, 

for example for cooking food, cannot be achieved by heat pumps or recovery there may be 

many uses for lower grade heat, such as pre-heating boiler feed water or heating wash water 

for the production area. When the application is collecting and redirecting waste heat from a 

refrigerating system it is called heat recovery. When it is performing a non-productive 

chilling process on a source of heat, whether it is at ambient temperature or is the waste heat 

stream from another process such as a cooker flue, it is a heat pump. 

Large heat pumps have also been used for heating public buildings, for example in 

Gardermoen Airport, Norway (8100kW heating capacity) and Akershus hospital, Norway 

(8000kW heating capacity). These systems are custom-designed, using R-717 as the 

refrigerant /Ste08/. 

Even larger systems are used for district heating systems, with many examples in 

Scandinavia. The smallest of these systems are about 5000kW. Most installations use HFC-
82 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

134a in centrifugal compressors, with some (up to 15000kW) using R-717. The largest is in 

Stockholm, with a total capacity of 180000kW (180MW) using HFC-134a in centrifugal 

compressors. This system takes heat from sea water to provide the thermal source; other 

similar installations have used waste water from the sewage system /Bai06/. 

5.2.5 Leisure 

The principal use of refrigeration in the leisure market is for ice rinks, extended also to indoor 

ski-slopes, ice climbing walls and other ice features. Many older ice rink systems used direct 

CFC-12 or direct R-717. To change to an indirect system would require replacement of the 

floor slab, which is a considerable capital expenditure. Some CFC-12 systems have been 

converted to HCFC-22 despite the increased pressure. Similarly some R-717 systems in 

Central Europe have been converted to R-744. A few very large systems have been installed 

for bobsled and luge runs, typically associated with winter Olympics. These systems usually 

use pumped R-717. A recently installed cross-country ski track in Finland used R-744 for the 

track cooling, with circuits up to 1km long. 

5.2.6 Process Refrigeration 

Cooling is used in a wide variety of process applications (in addition to food industry 

applications covered in section 5.2.1). The cooling can be applied by a direct refrigeration 

system with a coil in the process tank, or a jacket around the outside of a chemical reactor 

vessel or storage tank. Alternatively a secondary fluid such as water, brine solution or glycol 

may be used. In these cases standard chillers as described in chapter 9 might be used, 

although there may still be other reasons for requiring the chiller to be specially designed for 

the project. 

5.3 Working Fluid Options for New Equipment 

5.3.1 R-717 (Ammonia) 

The analysis of evaporative condenser use shown in Table 5-1 indicates that R-717 is by far 

the most common refrigerant used in industrial systems. The major hazard presented by R717 is its acute toxicity, although its pungent odour ensures that low, relatively harmless 

concentrations are obvious and provide an early warning of danger. 

R-717 is flammable in relatively high concentrations, but it is difficult to ignite and as a result 

R-717 conflagrations are extremely rare. The products of combustion are nitrogen and water, 

so there are no toxic consequences. The lower flammable limit is 16%; about 5,000 times 

higher than the short term exposure limit, and almost 50,000 times higher than the lowest 

level which can be detected by smell. 

R-717 systems can be designed for very high efficiency, particularly with higher condensing 

temperatures, so in recent years it has been used more often in smaller systems with air cooled 

condensers, condensing at about 50o

C /IIR08/. Compression of R-717 produces relatively 

high compressor discharge temperatures compared with most fluorocarbons, but if oil injected 

screw compressors are used then the heat of compression can be removed by oil cooling. R717 also produces relatively high heat transfer coefficients and requires a low massflow due 

to its high latent heat. The high critical temperature of 133o

C makes R-717 very suitable for 

high temperature heat pumps. It is at atmospheric pressure at -33o

C, a relatively high 

temperature for industrial freezers. This means that many freezers operate at sub-atmospheric 

pressure, so air and moisture are drawn into the system if it is not pressure-tight on the low 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 83

pressure side. This unfortunate consequence is generally tolerated because the moisture is 

soluble in ammonia liquid so does not immediately cause unreliability and because both air 

and water can be relatively easily removed from the system while it is in operation. However 

excessive water build up will eventually impair operating efficiency and therefore increase 

electrical consumption, so system contamination should not be left uncorrected /Nie00/. 

5.3.2 Hydrofluorocarbons 

When the first HFC refrigerants, particularly HFC-134a, were introduced in the late 1980s to 

replace CFC-12 there was no obvious successor to the most common CFC blend in the 

industrial market, R-502. This had been introduced to enable single stage compression plants 

to be used for low temperature applications without excessive discharge temperatures. When 

it became clear that R-502 could no longer be used, because it contained CFC-115, most 

system designers either used HCFC-22 or R-717, both of which produced higher discharge 

temperatures and therefore required additional cooling or two compression stages for freezer 

applications. 

Saturated: Saturated hydrofluorocarbons include fluids such as HFC-134a and HFC-125 and 

blends of fluids, mixed to provide specific advantages for particular applications. HFC-134a 

is used in small high temperature systems; it is at atmospheric pressure at -26o

C, and it 

requires larger compressors than R-717. Sub-atmospheric operation is less common with 

HFCs because traces of moisture are liable to freeze and block the expansion valve. 

HFC-134a is also widely used in centrifugal compressors, including some very large systems 

used for district heating. There is currently no alternative to HFC-134a in this technology. 

There is no single fluid alternative to HCFC-22 for use in industrial systems. HFC-125 has 

approximately the right pressure temperature relationship, but has an extremely low critical 

temperature of 66o

C, and would therefore be extremely inefficient if used in industrial 

systems, unless the condensing temperature was very low. It is used as a component of 

several of the most popular blended refrigerants, where the deficiencies in its physical 

properties can be offset by careful selection of the other components of the blend. The most 

common blends used in the industrial sector are R-404A and R-507A, which are primarily 

mixtures of HFC-125 and HFC143a; with the latter providing a higher critical temperature 

and hence improved efficiency. Many industrial systems use flooded evaporators, where the 

refrigerant boils in a pool. Zeotropic blends (with a temperature glide during evaporation) are 

not suitable in these systems because the blend components may fractionate, so R-407C and 

service replacement blends such as R-417A have not been much used in the industrial sector. 

It is surprising that R-410A has not been more widely used in industrial systems because it 

has a low boiling point at atmospheric pressure (-51.4o

C), very low glide (less than 0.2K at -

40 oC) and the critical temperature is almost the same as R-404A. The compressor swept 

volume required for R-410A is about 30% less than for R-404A, so equipment costs, 

including installed pipework should be less, although operating pressures are higher. The 

main barrier to its use is probably the high price of the refrigerant, particularly compared to 

R-717 and R-744. When the refrigerant inventory in a system is in tonnes the cost of the 

charge may be a significant part of the total cost of the installation. Typical installations are 

therefore low capacity, low temperature, for example blood freezing and small pharmaceutical 

systems. 

Unsaturated: unsaturated hydrofluorocarbons such as HFC-1234yf and HFC-1243zf have not 

to date been used in industrial systems. The low global warming potential suggests that they 

may be a suitable alternative to R-717 and R-744, but it is very likely that they will be even 

more expensive than R-410A, with the further disadvantage of being flammable. It is 
84 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

therefore likely that none of this family of chemicals will achieve any significant market 

penetration in the industrial sector, even if blended with other compounds to reduce price or 

flammability. 

5.3.3 HCFC-22 

Where its use is still permitted in new systems, particularly in article 5 countries, HCFC-22 is 

still common. It has not been supplanted by HFC blends because it is cheaper than any of the 

blends and usually offers better system efficiencies. Where HCFC-22 was widely used in 

smaller industrial and heavy commercial systems and has subsequently been superseded by R404A, which has a significantly higher global warming potential. 

5.3.4 Hydrocarbons 

Hydrocarbons are not widely used in industrial refrigeration except where the additional 

safety measures required to ensure that leaking refrigerant cannot be ignited are required 

anyway, for example in a petrochemical plant. They offer excellent efficiency, and 

compatibility with most materials and lubricants. However the precautions required to 

prevent ignition are significantly more expensive than those required for R-717 systems. HC290 is generally similar to HCFC-22 and R-717 in terms of operating temperatures and 

pressures, and requires similarly sized compressors. 

5.3.5 R-744 (Carbon dioxide) 

R-744 cannot be used in exactly the same way as other industrial refrigerants. It needs to be 

coupled with a higher temperature refrigerant in a cascade system due to the low critical 

temperature of 31o

C or else used in a transcritical system. Transcritical systems have been 

used in commercial and small systems, but there are no compressors on the market to provide 

the necessary high operating pressures to run an industrial R-744 system in this way. A 

medium-sized distribution centre with an installed capacity of 1500kW has been operating in 

Denmark since 2008, using multiple commercial-sized compressors /Mad09/. 

R-744 is particularly suitable for use in freezer systems because it is at positive pressure down 

to -56o

C and the gas is extremely dense, giving very high rates of heat transfer. The pressure 

drop characteristics are also very favourable at low temperatures, so R-744 freezer systems 

have been found to be significantly more efficient than any other alternative, even R-717 

/Pea09/. In slightly higher temperature applications, such as cold storage, R-744 cascade 

systems are likely to be slightly less efficient than two-stage R-717, but still on a par with a 

single stage economised system, and more efficient than any system using a secondary fluid 

due to the much lower pumping cost for R-744 compared to glycol, brine or other heat 

transfer fluids /ASH10/. 

In higher temperature applications, for example IT cooling, R-744 is attractive as an 

alternative to chilled water because it is electrically non-conductive, does not cause fabric 

damage in the event of a small leak and enables smaller heat exchangers to be used. The 

major challenge in these systems is that the operating pressure is approximately 50 bar. 

5.3.6 R-718 (Water) 

In general R-718 is not suitable for most industrial applications because the triple point is 

very slightly above 0o

C, and because, despite the very high latent heat, the swept volume 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 85

required for a typical cooling duty is extremely high. There are a few notable exceptions: R718 has been used for a few deep mine cooling projects where a vacuum system is used to 

create a mix of solid and liquid water (ice slurry) at the triple point. Similar systems have 

been used for large plastics moulding coolers, but these systems have not yet been fully 

commercialised. 

5.3.7 Absorption 

Absorption systems using aqua-ammonia can be used for low temperature applications, easily 

reaching cold storage temperatures. This is because the ammonia is used as the refrigerant, 

with water as the absorbent. Water-lithium bromide (LiBr) systems can only be used above 

freezing because the water is the refrigerant, and the LiBr is the absorbent. Absorption 

systems are only effective if there is an abundant source of heat at high temperature to drive 

the system. It is not normally economic to burn fossil fuel for the sole purpose of driving the 

regenerator of an absorption system, particularly in low temperature systems, because the heat 

rejection plant is significantly larger then for an equivalent duty, electrically driven vapour 

compression system. 

Absorption systems are primarily used for process cooling in food, beverage, chemical and 

pharmaceutical plants where waste heat to drive the system is readily available. There is an 

increase however in the food industry, when local on-site power generation is used, and 

provides a source of waste heat. This has been particularly noted in developing countries 

such as India and China, where increased food production is being achieved but the electrical 

infrastructure is still relatively unreliable. In these cases chilling is normally achieved with 

vapour compression plant, but with some absorption cooling available to augment the cooling 

capacity when the generator is running. 

5.4 Retrofit Options for Existing Equipment 

Systems using HCFC-22 have been converted to zero ODP refrigerants, but it is difficult to 

replicate the operating conditions of HCFC-22 and so conversions often involve an element of 

equipment replacement. Before committing to any large scale retrofit project consideration 

should be given to the age of the plant, the cost of replacement with a modern, more efficient 

system and the risks to continued operation of retrofit. 

5.4.1 Conversion to HFC Blends 

There are numerous blends for the replacement of HCFC-22 in DX (superheat controlled) 

systems, but there is none that replicates the pressure temperature relationship of HCFC-22 

without significant glide, and so these blends are much less common in flooded systems 

where fractionation of the blend is a concern. Where industrial systems are converted to a 

blend it may also be necessary to change from mineral or alkyl benzene lubricant to a 

synthetic ester. Some blends are formulated with hydrocarbons in the mix so that, although 

still non-flammable, the lubricant is more miscible and less likely to accumulate in the 

evaporator of the system. For a large flooded system it might be appropriate to convert the 

compressors and condensers to an HFC blend, but convert the low pressure side to a 

secondary fluid, or even R-744 as a volatile secondary. Retrofitting of HCFC-22 plant in 

Article 5 countries is very uncommon to date. 
86 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

5.4.2 Conversion to R-744 

The high operating pressure of R-744 systems makes it highly unlikely that an existing 

HCFC-22 system could be converted to operate on R-744. Conversion to a cascade system is 

possible, greatly reducing the inventory of fluorocarbon refrigerant in the system. It may 

even be possible to reuse the low pressure pipework and evaporators in the system if they are 

suitably rated. A cold storage or freezing system operating as a cascade on R-744 could be 

limited to an allowable pressure of 25 bar gauge, however this is a complex retrofit and it may 

well be more economic to replace the whole plant, especially if it is already more than ten 

years old. 

5.4.3 Conversion to R-717 

In a very few cases a pumped HCFC-22 plant has been converted to R-717. Usually the 

compressors and condensers are suitable for either refrigerant, and pipework is probably 

welded steel in large applications. If the evaporators are copper tube then they need to be 

replaced. It is imperative that the system is carefully cleaned during the conversion because 

any residual traces of HCFC-22, for example in lubricant will react with R-717 to produce a 

solid foam which can block all the internal components. Triple evacuation with nitrogen 

purging is probably necessary – this is time-consuming and expensive and again plant 

replacement should be considered. In the majority of cases, in all countries, equipment using 

HCFC-22 is not suitable for this conversion. 

5.4.4 Conversion to Hydrocarbon 

Unlike R-744 and R-717 it is technically feasible to remove HCFC-22 from existing systems 

and replace it with HC-290, however it is highly likely that the resultant system will not 

comply with safety codes on the use of hydrocarbons because the refrigerant quantity will not 

comply with charge restrictions and the electrical infrastructure will not be suitably protected. 

A conversion of this type is believed to have been responsible for a fatal accident in New 

Zealand in 2008 /New08/. A consequence of rapid phase out of HCFCs in Article 5 countries 

might be an increase of this type of conversion without adequate controls. There is however a 

case for a controlled conversion from HCFC-22 to HC refrigerant (propane or isobutane) 

where the system efficiency can be improved. In this case it is essential that suitable safety 

measures are ensured. 

5.5 Overview of Refrigerant Consumption, Banks and Emissions 

It is difficult to estimate the size of CFC, HCFC and HFC banks associated with the industrial 

sector because the technology is used in a very wide range of applications. A report 

published by ADEME in 2010 /ADE10/ provided estimates based upon published data from 

various food sectors as collated by the Food and Agricultural Organisation of the United 

Nations. This report indicated that the total demand for refrigerants in the industrial sector 

was about 50,000 tonnes, with HCFCs accounting for about one-half of this. The remainder 

of the demand was approximately 15,000 tonnes of ammonia, 5,000 tonnes of CFCs 

(principally in Article 5 countries) and 5,000 tonnes of HFCs, principally in Europe. The 

estimated size of the banks of refrigerant within existing equipment ranges from 3.5 times the 

demand to 7 times the demand. 

The emissions figures for refrigerant type and region are also very difficult to estimate. They 

range, as a percentage of the bank for each region, from 4% to about 21%, with the exception 

of CFC emissions, which are estimated to be 27.7% of the total bank. This is presumably a 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 87

result of the condition of the residual equipment still using CFCs, and suggests that there is a 

strong imperative to incentivise a switch to alternatives as quickly as possible, provided the 

old refrigerant is recovered and reprocessed. 

A summary of the approximate figures for 2006 is given in tables 5-4 to 5-7. 

Table 5-4: Refrigerant Demand in 2006 

Demand (tonnes) USA Europe Total 

CFC 0 0 5,563 

HCFC 1,446 1,290 25,372 

HFC 1,087 2,405 4,707 

R-717 3,845 2,930 15,667 

Table 5-5: Refrigerant Banks in 2006 

Banks (tonnes) USA Europe Total 

CFC 3 13 19,896 

HCFC 12,681 15,819 93,985 

HFC 7,681 17,498 30,735 

R-717 26,401 20,533 105,923 

Table 5-6: Refrigerant Emissions in 2006 

Emissions (tonnes) USA Europe Total 

CFC 0 0 5,512 

HCFC 1,106 1,390 20,229 

HFC 628 1,261 2,521 

R-717 1,226 800 9,408 

Table 5-7: Refrigerant Emission as a percentage of the bank in 2006 

Emissions (%) USA Europe Total 

CFC - - 27.7% 

HCFC 8.7% 8.8% 21.5% 

HFC 8.2% 7.2% 8.2% 

R-717 4.6% 3.9% 8.9% 

It is difficult to reconcile these figures with other published data, which suggests, for example 

that the R-717 refrigeration market is much larger than this. Given the characteristics of the 

substances it also seems unlikely that the percentage leakage rate of R-717, which has a 

characteristic pungent smell, would be higher than the leakage rate for odourless HFCs. 

Other studies report much higher leakage rates for HFCs, noting that poor workmanship 

during installation can result in higher leak rates during the first few months of operation until 

all problems have been resolved. 
88 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

5.6 Service Requirements 

Given the difficulty of converting from HCFC-22 to zero ODP refrigerants, many users with 

multiple systems have planned a replacement strategy to conserve their stock of refrigerant. 

Setting priorities for which system to replace or convert first includes consideration of age of 

the plant, likelihood of leakage and ease of conversion. Refrigerant which is recovered from 

converted systems can be recycled and stored on site to be used in the remaining plants. In 

Europe, where service with “virgin” HCFC-22 was prohibited from the beginning of 2010, 

some users have banked additional refrigerant by overcharging their plants with new HCFC22 prior to the end of 2009 and then recovering the excess refrigerant, which is then classed as 

recycled. This practice is not strictly outside the law, but it is not in the spirit of the 

regulation. It probably accounted for some additional sales of HCFC in the two years leading 

up to the prohibition, keeping sales artificially high at a time when many plants were being 

converted or decommissioned. If other regions implement similar regulations for the phase 

out of HCFCs they should consider ways to plug this loophole, for example by limiting the 

time that recovered HCFC can be stored before it is used, and requiring it to be sent for 

destruction or reprocessing if it is not used within the timeframe. This was done in Ireland, 

and greatly improved the effectiveness of the restriction on virgin HCFC-22. 

5.7 References 

/ADE10/ Global inventories of the worldwide fleets of refrigerating and airconditioning equipment 

in order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES, April 2010 

/ASH09/ Design Considerations for Datacom Equipment Centers, Second Edition, ASHRAE, 

TC9.9, Atlanta, 2009 

/ASH10/ ASHRAE, “Refrigeration Handbook, chapter 3”, Atlanta, 2010 

/Bai06/ Bailer, P. and Pietrucha, U., “Design And Application Of Ammonia Heat Pump Systems 

For Heating And Cooling Of Non-Residential Buildings” 10th International Symposium on 

District Heating and Cooling, Hannover, 2006 

/Bra08/ Brasz, J., “Assessment of C6F as a working fluid for Organic Rankine Cycle 

Applications”, Int. Conf. on Refrigeration and Air-Conditioning, Purdue University, 2008 

/Bro92/ Brown, A. H., “Return to Ammonia?” Institute of Refrigeration, London, 1992 

/Hut05/ Hutchins, G., “Mission Critical Cooling” Institute of Refrigeration Annual Conference, 

London, 2005 

/IIR08/ International Institute of Refrigeration, “Ammonia as a Refrigerant, 3rd Edition”, IIR, 

Paris, 2008 

/Les09/ Leslie, N., Sweetser, R., Zimron, O. and Stovall, T., “Recovered Energy Generation Using 

an Organic Rankine Cycle System” ASHRAE Transactions Vol. 115 Part 1, Atlanta, 2009 

/Mad09/ Madsen, K “Living without HFCs: the Danish Experience”, Institute of Refrigeration, 

London, 2009 

/Nie00/ Nielsen, P.S., “Effects of Water Contamination in Ammonia Refrigeration Systems, 

Danfoss, Nordberg, 2000 

/New08/ New Zealand Fire Service Report No F128045 “Inquiry into the Explosion and Fire at 

Icepak Coolstores, Tamahere, on 5 April 2008”, 2008 

/Pea09/ Pearson, A.B., “Calculating Freezing Times in Blast and Plate Freezers”, International 

Institute of Ammonia Refrigeration, Dallas, 2009 

/Ste08/ Stene, J., “Design And Application Of Ammonia Heat Pump Systems For Heating And 

Cooling Of Non-Residential Buildings” Proc GL2008, IIR, Copenhagen, 2008 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 89

/Suz05/ Suzuki, Takeuchi, Masuda, Watanabe, Shirakashi, Fukuda, Tsuruta, Yamamoto, Koga, 

Hiruma, Ichioka and Takai. "Test report on effectiveness of magnetic field for food 

freezing process" Tokyo University of Marine Science and Technology, 2005 

/UNE10/ UNEP Technology and Economic Assessment Panel, Task Force Decision XXI/9 Report, 

“Assessment of HCFCs and Environmentally Sound Alternatives Paragraph 2C”, May 

2010 

/Zyh03/ Zyhowski, G., “Opportunities For HFC-245fa Organic Rankine Cycle Appended To 

Distributed Power Generation Systems”, Int Congress of Refrigeration, IIR, Washington 

DC, 2003

2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 91

Chapter 6 

__________________________________________________________ 

Transport Refrigeration 

Chapter Lead Author 

Radim Čermák 

Co-Authors 

Michael Kauffeld 

Alexander C. Pachai 

Contributors 

Yves Wild 

Gerald Cavalier 

Ruhe Xie 

Daniel Colbourne 

Petter Nekså
92 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

6 Transport Refrigeration

6.1 Introduction 

Transport refrigeration includes transport of chilled or frozen products by means of road 

vehicles, railcars, intermodal containers, and small insulated containers (less than 2 m3

) and 

boxes. It also includes use of refrigeration and air conditioning on merchant, naval and fishing 

vessels above 100 gross tonnes (GT) (about over 24 m in length). 

Technical requirements for transport refrigeration systems are extremely complex. The 

equipment has to operate over a wide range of ambient temperatures and weather conditions 

(wind, solar radiation, rain, sea water spray, etc.). The equipment has to be able to carry any 

one of a wide range of cargoes with different temperature needs and even different 

temperatures simultaneously in different compartments (more than 20 % of the European 

market for truck and trailers). 

All transport refrigeration systems have to be very robust and reliable to withstand vibrations 

and shocks. At the same time, the systems must be compact to maximise cargo space, and 

lightweight to reduce the energy required to move the vehicle. 

It is imperative that spare parts (including refrigerant) are available along transport routes 

world-wide. Returning to a port can be a major issue for marine vessels in case of a 

refrigeration plant breakdown. This must be considered when design changes and 

improvements are made and introduced. Rigorous testing must be carried out so that only 

proven reliable systems are commissioned for field use. 

Despite these efforts, refrigerant leaks inevitably occur within the refrigeration systems 

because of vibrations and shocks, and sometimes because of collisions with other objects. In 

addition, the harsh environmental conditions tend to accelerate the equipment aging. The 

equipment lifetime is usually between 10 and 15 years for road vehicles, railcars and 

intermodal containers, or less than 10 years in case of intensive use, and 20 to 25 years for 

merchant, naval and fishing vessels. 

Safety is a number one priority in all transport refrigeration systems, because trained and 

certified service personnel may not be available along transport routes. Safe operation is 

particularly essential in the case of marine vessels, where evacuation is difficult or impossible. 

Safety must be either inherent in the fluids, or must be ensured through a number of technical 

measures. 

6.2 Technical Progress 

6.2.1 Merchant, Naval and Fishing Vessels 

There are enormous differences between vessels in terms of category, tonnage, length etc. 

Some of the main markets are ferries, cruisers, container ships, reefers, trawlers, fish factory 

ships, submarine navy, surface navy, tankers, and bulk carriers. 

The overall size of a ship is measured in terms of gross tonnage, which also forms the basis 

for manning regulations, safety rules, registration fees, etc. Unless stated otherwise, data 

presented in this report are limited to vessels above 100 gross tonnes (GT), or about over 24 

m in length. It is assumed that nearly all vessels above 100 GT have refrigeration systems for 

their provision rooms and air conditioning for the occupied cabin space. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 93

A relationship between the vessel category, tonnage and use of refrigeration (refrigerant, 

charge) is difficult to establish mainly because of a limited access to registry statistics. 

Instead, although less accurate, our estimates of banks and emissions are based on a number 

of vessels and their refrigerant charge on average. 

Merchant (or commercial) vessels include in principle cargo ships, passenger ships, and 

special-purpose ships. According to Equasis /Equ07/, the world merchant fleet amounted to 

72,000 vessels with 780 million GT combined. 86 % were small and medium size ships below 

25,000 GT. About 3,000 merchant vessels were above 60,000 GT. According to another 

source, the 2009 Review of Maritime Transport /Rev09/, the world merchant fleet is a little 

below 100,000 vessels. 

Reefer ships are one category of merchant ships – used for transport of perishable 

commodities such as fresh or frozen food. At the end of 2008, the total reefer fleet stood at 

about 1,000 /IIR09/. There were 137 reefer ships in EU registers in 2009. This number was 

predicted to decrease to about 50 by 2020 /Tec09/. Instead, the share of goods transported by 

means of intermodal containers will continue to increase, hand in hand with the expansion of 

the fleet of container ships /Rev09/. 

The fleet of naval ships is difficult to estimate. The US Navy /Nav10/, largest in the world, 

operated 290 ships in active service as of August 2010. The world fleet of naval ships is 

estimated to be less than 5,000. 

There are about 4 million fishing vessels of various types in operation, of which one third are 

decked. The average size of decked vessels is about 20 GT (around 10-15 m). Those larger 

than 100 GT amounted to 50,000 units. China has approx. 50 % of these larger vessels 

/FAO10/. At the end of 2009, the EU Fleet Register listed some 3,700 fishing vessels greater 

than 100 GT /Tec09/. 

Regulation of refrigeration systems in ships is typically a flag state right, which implies that 

the ship owner may change the flag state should any restrictions be imposed in the current 

flag state. On the other hand, if a ship arrives to a country where a group of refrigerants is not 

allowed, refrigerant availability can be an issue in case of a refrigerant loss. 

In 2009, 93 % of the worlds merchant fleet in terms of deadweight tonnage, or dwt (= loaded 

ship displacement minus the lightship weight) registered under the flag of 35 countries and 

territories. The top registries (by dwt share) were Panama, Liberia, Marshall Islands, Hong 

Kong (China), Greece, Bahamas, Singapore and Malta, accounting for 65 % of the world’s 

dwt /Rev09/. 

More than two thirds of fishing vessels in operation in 2007 were registered in countries in 

which they were also built. The major registries for fishing vessels have been China, Japan, S. 

Korea, Peru, the Russian Federation, Poland, Spain, and USA /FAO07 and Ana99/. 

Air pollutant emissions from ships are covered by Annex VI of the Marine Pollution 

Convention, MARPOL 73/78, of the International Maritime Organization /Mar10/. MARPOL 

Annex VI (reg 12) prohibits new installations containing ozone-depleting substances on all 

ships from May 19, 2005, but new installations containing HCFC refrigerants are permitted 

until January 1, 2020. As of 31 July 2010, there were 60 contracting states which represent 84 

% of the world tonnage. 

For developed countries, the Montreal Protocol has introduced a stricter regulation of HCFC 

fluids than MARPOL. For example, Regulation (EC) No 2037/2000 of the European 

Parliament prohibits the use of HCFC refrigerants in new equipment from 2002 onward; 
94 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

HCFC will be allowed for maintenance of existing equipment only until 2015 and only with 

recycled HCFC from beginning of 2010. 

HCFC-22 has been the dominant refrigerant used aboard ships (80 % of present fleet). It has 

been used universally for air conditioning systems, cooling and freezing of food for 

passengers and the crew, and in the holds and in the production on trawlers and factory 

vessels. HFC refrigerants have been replacing HCFC-22 in new-built ships following the 

phase out of ozone-depleting substances under the Montreal Protocol. 

HFC-134a has been the most often used alternative to HCFC-22 in new vessels for both air 

conditioning and refrigeration. R-404A and R-407C have been used mainly to retrofit HCFC22. New ships may also use R-410A going forward, as it is becoming widespread in other 

fields. HFC-23 is used for freezing at -60 °C and below (mainly fish). Natural refrigerants 

have been used in a relatively few vessels; primarily larger trawlers and reefers (see section 

6.4). The current share of HFC refrigerants in the world’s fleet is estimated at 10 %. 

A typical refrigerant charge for vessels above 100 GT is between 100 and 500 kg for direct 

systems, and between 10 and 100 kg for indirect systems. The annual refrigerant leakage rate 

could be as high as 20 - 40 %. 

There has been a trend to build fewer larger ships rather than a larger quantity of smaller ships 

in many categories – fish carriers /Stao07/, oil tankers, bulk carriers /Rev09/. One reason 

could be the recent increase in fuel prices. 

6.2.2 Road Transport 

The road refrigeration market comprises several vehicle segments: small trucks and vans with 

a cargo volume below roughly 19 m3

, large trucks with a volume between 20 and 59 m3, and 

trailers and semi-trailers with a box volume up to more than 100 m3

. Small trucks and vans 

are used predominantly for distribution in urban and sub-urban areas, while long haul 

transport favours large trucks and trailers. 

The total world fleet is estimated at 4,000,000 vehicles, of which about 30 % are trailers, 30 

% are large trucks and 40 % are small trucks and vans. The portion may vary from region to 

region. It is predicted, for example, that the total fleet of temperature controlled trucks in 

China will reach 80,000 in 2010. There are estimated 100,000 refrigerated trucks in Japan and 

more than 100,000 in France. Each vehicle is typically equipped with a single refrigeration 

unit. 

It is common to state the maximum refrigeration capacity at two or three operating conditions 

that represent frozen cargo and chilled (perishable) cargo. The exact rating conditions vary 

slightly for different markets and countries: the North American market prefers to rate at box 

temperatures of –17.8 oC and 1.7 oC at an ambient temperature of 37.8 oC, while the countries 

committed to the ATP Agreement /Agr10/ prefer the box temperatures of –20 oC and 0 oC at 

an ambient temperature of 30 oC. 

For 15 years multi-temperature equipments have been developed. They allow the same 

vehicle with only one refrigeration unit to carry products at different temperatures in 2 or 3 

compartments. They represent more than 30 % of the European market for new equipment, 

and some 20 % of current fleet. Some operators purchase only the multi-temperature 

equipment even if they often operate in mono-temperature mode. 

If the exact rating conditions and the vehicle type are neglected, the maximum refrigeration 

capacity ranges from less than 500 W up to 10 kW at the frozen cargo temperatures and from 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 95

less than 1 kW up to 20 kW at the chilled cargo temperatures. The refrigeration capacity 

during transportation varies with the actual heat load. Most units are able to provide heating 

in the cargo box, usually by means of hot gas (compressor discharge), electricity, or 

independant gas heating equipment. 

Power supply management and power transmission management can give the largest 

differences in design of refrigeration units for trailers, large trucks and small trucks or vans. 

Small truck units are typically driven directly from the vehicle engine. Very small units (for 

vans) may be powered by a DC power from the battery and alternator of the vehicle. Large 

trucks and trailers are powered by an independent, usually diesel engine, which is integrated 

inside the unit. In order to eliminate exhaust emissions, most units also include an electrical 

motor that can drive the compressor from the electricity grid at stops. Power can be 

transmitted from the engine to the loads either mechanically or electrically. The mechanical 

solution relies on mechanical coupling between engine and an open drive compressor, while 

in the electric solution the engine drives a generator which powers a hermetic or semihermetic compressor and fan motors. The use of hermetic compressor significantly reduces 

refrigerant leaks, with obvious benefits. 

The refrigerant charges are between several hundred grams and 10 kg, usually less than 6 kg 

for small and large trucks. Although small truck units have a lower capacity than large truck 

units, they include refrigerant hoses that connect the unit with the compressor mounted on the 

engine block. Trailer units may have a typical refrigerant charge around 7.5 kg. Refrigerants 

typically used are R-404A and HFC-134a, but also R-410A or R-407C. 

There is an ongoing effort in the industry to reduce the greenhouse gas emissions. This is 

being realised through a number of complementary steps, including design changes that 

would improve the energy efficiency, reduction of the refrigerant charge and the refrigerant 

leakage rates, use of low-GWP refrigerants, and transition of power supply systems from 

traditional diesel engines to alternative propulsion systems (hybrid, electric, etc.). 

6.2.3 Railcars 

On a global scale, refrigerated railcars have become a very scarce type of vehicle used for 

transport of perishable and frozen product. There is a clear and definite trend to replace the 

refrigerated railcars with mobile boxes or intermodal refrigerated containers that can be, if 

railway is to be used, placed on a flat car. In some countries two containers can be transported 

on one railcar (one on the top of the other). Transport by rail is used mainly for long 

distances. 

It is estimated that there are no more than 20,000 refrigerated railcars used globally (7,000 in 

the former Soviet Union, 2,000 in China, 7,000 in USA, 2,000 in the European Union and 

2000 in the rest of the word). This is roughly one fifth of the global demand for new 

intermodal refrigerated containers in one year. 

A factory in Eastern Germany since 1945 exported nearly 42,000 railcars to the former Soviet 

Union, and over 12,000 railcars to China and other states in Europe /Kue09/. Today, a 

company leading the Russian perishables transportation market operates 3,500 refrigerated 

railcars /Ref09/. In China, production of refrigerated railcars with water ice closed down in 

1993, production of mechanically refrigerated railcars closed down in 2003, and the fleet is 

being gradually phased out. At present, there are about 2,000 cars with 4,000 refrigeration 

units in operation in Europe. A European network named Interfrigo reported just 285 

refrigerated railcars in 2002 /Sch09/. In 1987, Interfrigo used to manage nearly 19,000 railcars 

of all types. A few railcars may still be operated by individual European railways. In USA it 

was estimated that the supply of refrigerated rail cars would decrease from about 19,000 in 
96 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

1980 to about 5,000 by 1990 /Hil80/. According to /All00/, a major railway company 

managed 5,200 refrigerated railcars, constituting about 70 % of the entire US fleet in 2000. 

All mechanically refrigerated railcars in service utilise the vapour compression cycle. In terms 

of design, the refrigeration systems are similar to those employed in road transport and 

intermodal containers. The refrigerants used were CFC, HCFC, and HFC for the newest 

systems. In China, CFC-12 is being replaced by HCFC-22 gradually since 2008. More than 

ten eutectic plate refrigerated railcars were manufactured in China, however, they did not 

proceed into serial production. 

Not all railcars used for transport of perishable and frozen products are mechanically 

refrigerated. Many railcars have used water ice to maintain the temperature – they are 

dependent on ice banks along their routes. Many cars have been only insulated. None of these 

types have been considered in this section. 

6.2.4 Intermodal Containers 

The size of intermodal refrigerated containers has been standardised /ISO08/. The weight of 

the heaviest cargo limited the size of the first containers to about 6 m (20 ft). As most cargo is 

somewhat lighter, 12 m (40 ft) containers have been developed. 40 ft containers are today 

used to a greater extent than 20 ft containers. Containers differ also in height, but the 

difference in height is small compared to the length. 

The volume of cargo transported is commonly expressed in terms of Twenty-foot Equivalent 

Units, or TEU. A 40 ft container equals roughly to 2 TEU, but is refrigerated by a single 

refrigeration system just like the 20 ft container. The difference in size makes it difficult to 

estimate the global fleet, because statistics usually describe the total TEU regardless of the 

container size. 

Data of intermodal refrigerated containers is available only for those still being used in ocean 

traffic. It is not known how many refrigerated containers are still in use on landside 

applications after they were retired from ocean traffic. 

In 2009, there were approximately 150,000 units of 20 ft containers and 800,000 units of 40ft 

containers in use. The total number of units in operation was thus 950,000 (or 1,750,000 

TEU). At the beginning of 2009 /Rev09/, there were 4,638 fully cellular container ships, with 

a total capacity of 12 million TEU (all cargo, not only refrigerated). Up to 100,000 new 

refrigerated containers were built annually until the year 2007. This number has dropped as a 

consequence of the global economic recession in the years following 2007. 

The vapour compression cycle has been the only technology used in intermodal refrigerated 

containers. First systems utilised CFC refrigerants and some HCFC refrigerants, but new 

systems today utilise only HFC-134a, or HFC blend R-404A (approx. 10-15 %). Four 

manufacturers dominate the global market. 

All container units are electricity driven due to availability of electric grid on ships. When 

used on land (trailers, flat railcars, etc.), electricity is supplied from the electric grid or from a 

diesel engine generator set that is mounted on the unit front or the trailer. 

The refrigeration performances can be tested according to ISO 1496-2:2008. The maximum 

refrigeration capacity is commonly stated at three operating conditions that represent frozen 

cargo and chilled (perishable) cargo. The maximum refrigeration capacity is around 4 kW at a 

box temperatures of –29 oC, around 6 kW at a box temperatures of –18 oC, and it is around 12 

kW at a box temperatures of 2 oC, all rated at the ambient temperature of 38 oC. All units are 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 97

able to transport any type of cargo in any climates. This means that both refrigeration and 

heating must be supplied. 

Approximately 60 % of new units are fitted with hermetic scroll compressors offering many 

advantages including reliability, leakproofness, low weight, small size and low noise. The 

current technology features reduced refrigerant charges and emissions. The typical refrigerant 

charge is between 3.8 kg to 5.3 kg per unit with an average of approximately 4.5 kg. 

During the last years, there have been strong efforts to reduce the energy consumption of 

container units in order to reduce fuel consumption and carbon dioxide emissions. The 

controller reduces the amount of circulated air inside the container thus reducing fan power 

and consequently compressor power, too. For example, the fans are cycled between half and 

full speed instead of running continuously on full speed, or they are temporally switched off 

completely. 

Porthole type containers (insulated containers ventilated by chilled air refrigerated centrally) 

are not in operation any more and no new porthole containers, nor porthole container ships, 

are built. The last ships that offered refrigeration capacities for porthole containers have been 

converted for the transport of containers equipped with an integral refrigeration unit. 

China became the major producer of insulated marine containers (small productions are 

remaining in the world; for example in France, two manufacturers are building containers for 

military or NGO applications. There are three Chinese producers with a maximum annual 

production capacity of 230,000 TEU. 

6.2.5 Small Containers and Boxes 

The number of small containers may be equivalent to the number of other equipments in 

many European countries. On average, they transport a load of up to a few hundred kg. They 

are refrigerated mainly with solid carbon dioxide, but also with eutectic plates or small 

absorption or vapour compression units. 

Boxes are generally not reusable and refrigerated with eutectic sticks or solid carbon dioxide. 

They are widely used for transport of pharmaceutical products and samples of food products. 

Their use is increasing for direct distribution to the consumer of products bought online. 

Refrigeration by means of ice slurry in double walls of small containers and boxes is under 

development. 

6.3 Refrigerant Options for Existing Equipment

All new intermodal containers, majority of road vehicles and railcars, and many new 

merchant and fishing vessels use equipment with HFC refrigerants. HCFC refrigerants have 

been used in systems aboard vessels, and in older road and rail equipment. To retrofit HCFC 

refrigerants, only some refrigerant options will find its application in transport due to 

necessary service infrastructure and commonality of the working fluids. 

In road transport, R-408A, containing 47 % HCFC-22, is a retrofit solution for units that are 

currently using R-502. The retrofit to R-408A often improves system capacity and efficiency, 

while the compressor head pressure may slightly increase at high ambient environments. It is 

important that systems operating with R-502 and mineral oils may continue to use mineral 

oils provided the oil returns adequately to the compressor. If not, alkylbenzene or POE may 

be added (or used alone) to improve the miscibility and oil return. System components do not 

require changing when retrofitting. 
98 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

R-402A, containing 38 % HCFC-22, was used as a retrofit substitute for R-502 in the mid-tolate ‘90’s in the USA, and may be still used in some countries. 

Rather than R-408A or R-402A, it may be more suitable for some operators to retrofit with R404A. Although R-404A behaves much like R-502, several components incl. compressor may 

need to be replaced due to inferior lubricity of POE lubricant when compared to alkyl 

benzene, and marginally higher operating pressures of R-404A. Nevertheless, being an HFC 

blend, R-404A is a longer-term solution than R-408A. 

Aboard ships, R-407C and R-404A have been used most often to retrofit HCFC-22 in existing 

systems. These refrigerants have lower energy efficiency, but efficiency did not seem to be a 

major concern for many ship owners several years ago. Sometimes, HFC-134a has been used 

to retrofit HCFC -22 at the expense of losing about 30 % of refrigerating capacity. 

No natural refrigerant can be used to retrofit HCFC-22 without remodelling of the entire 

refrigeration system. Remodelling is often impossible due to existing layout and size of the 

refrigeration equipment. 

6.4 Refrigerant Options for New Equipment 

The vapour compression cycle will remain the dominant principle of refrigeration units in 

transport. HFC refrigerants will remain the preferred refrigerant options. Discussions about 

use of several new fluorinated refrigerants, such as HFC-1234yf, have recently taken place. 

These opportunities have not been considered in the present report – they have not been used 

commercially so far, and so no practical experience is available. 

Non-fluorinated refrigerants have received great attention over the last decade, and in several 

cases operational samples have been tested and presented to the public. However, various 

technical, legal, financial, logistic, service and other constraints have yet prevented a wider 

application of these new technologies in practice. Most applications of non-fluorinated 

refrigerants can be found aboard marine vessels. 

Hydrocarbons

Although hydrocarbons are technically feasible and may even outperform HFC systems, 

flammability makes people concerned about their use /Cor08/. Where they do not exist, 

standards need to be developed to address the safety concerns. 

Effort is being made to reduce the refrigerant charge through indirect systems and compact 

heat exchangers, outdoor placing of the units, leakage sensors and alarms and forced 

ventilation /Pal08/. Indirect systems are often penalised with a lower overall efficiency 

(higher fuel consumption), a greater complexity (reliability and maintenance cost), higher 

weight (fuel consumption) and larger size (cargo space), if compared with direct expansions 

systems. 

Equipment with charges of hydrocarbons greater than 1 kg is, in general, possible only if all 

the refrigerant containing parts are placed outdoors or in a special machinery room. Because 

these requirements cannot be met aboard marine vessels, HC refrigerants are not likely to be 

used there. 

HCs are currently trialled in trucks and home delivery vans in Great Britain and Germany, 

suggesting that their use may grow. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 99

Carbon dioxide 

Carbon dioxide (CO2, R-744) has the advantage that it is widely available world wide, but it 

must overcome several challenges before use in transport refrigeration is possible. Under high 

ambient temperature operation, sophisticated refrigeration cycles (two-stage cycles, work 

recovery devices, etc.) are necessary to match the system efficiency of equivalent HFC units. 

The cycle operation is almost always transcritical, which results in compressor discharge 

pressures up to 7 times higher than those in HFC systems. Therefore, entirely new parts, 

design approaches, test procedures, service training, etc. are needed to design, build and 

operate a transcritical R-744 system. The ability of using R-744 for heating in a heat pump 

cycle can be advantageous due to efficiency and capacity that is possible. 

Aboard ships, R-744 has been used in the subcritical state, either as a refrigerant with own 

compressors (second stage in a cascade), or a secondary coolant being circulated by pumps. It 

features excellent thermodynamic properties. When used in the second stage, it can cover the 

temperature range between -10 and -50 °C. HFCs or ammonia is used in the first stage. 

R-744 has a low temperature limit of about -54 °C and so it cannot be used, for example, on 

the Japanese market with requirements for fish freezing at -60 °C. Apart from that, R-744 in 

the subcritical state is suitable for ships, especially because it is not flammable and does not 

form aggressive or toxic products in contact with hot surfaces. It was reported /Tec09/ that R744 systems used in the second stage for freezing of fish and in reefer ships were able to save 

up to 25 % energy consumption compared to single stage HCFC-22 systems. 

No commercial solutions with transcritical CO2 are sold today in transport refrigeration. At 

least one manufacturer claims to field test transcritical R-744 units for marine containers in 

their full operating range. A trailer featuring a transcritical R-744 unit was presented at a 

recent international trade fair. Therefore, it is possible that commercial solutions will be 

available within the next few years. Because compressors, heat exchangers and other parts 

have special requirements in terms of robustness, weight, corrosion resistance, etc., vigorous 

performance verification must be carried out in order to qualify these systems for 

commercialisation. In addition, the energy efficiency in the transcritical operation mode has to 

be improved for hot climate applications. 

Ammonia 

Toxicity and flammability makes ammonia (NH3, R-717) a difficult option among alternate 

refrigerants for road vehicles, railcars and intermodal containers. The situation is different for 

marine vessels. 

From 2001, NH3 started to be used in large fishing vessels and in reefers in indirect and 

cascade systems. Meanwhile, classification bodies and authorities have widely ceased from 

their reservation towards NH3, in particular if exclusively professional personnel is on board. 

As for new-built fishing vessels and reefer ships, NH3 is of higher importance than HFCs 

today /Tec09/. 

The use of NH3 systems is limited to (1) ships that do not carry passengers but professional 

crew only (toxicity), and (2) ship with a relatively high refrigeration capacity (fishing vessels 

> 36 m) because of energy efficiency, safety and space reasons. Therefore, use of HFCs 

refrigerants will continue on cruise and passenger ships, and in general, on small ships of all 

categories. 
100 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Discontinuous systems 

Cryogenic (open-loop) systems have been applied in small and large trucks. In one system, 

liquid CO2 or N2 is stored in an insulated tank and injected to an evaporator via a vapour 

motor driving a fan. Other systems inject liquid N2 into the cargo space while displacing O2. 

Such systems require complex safety mechanisms and gas extraction equipment to protect 

operators (risk of asphyxiation). All cryogenic systems require recharging with liquid coolant. 

On the contrary, they offer low noise, reduced maintenance and outstanding refrigeration 

performance (fast pull-down), which make them excellent systems for vehicles serving local 

distribution chains. Two aspects shall be considered in energy analyses: the coolant 

consumption is proportional to the refrigeration need (diesel engines have always a minimum 

consumption), but energy is needed to produce the liquid coolants. 

Eutectic plates are sometimes utilised in distribution vehicles for short distances. They are 

based on a frozen salt solution, which, while it melts, removes heat from the environment and 

provides refrigeration. Low pull down capacity and somewhat inflexible temperature 

management makes them especially suitable for distribution of deep frozen products. 

Although they must be regenerated periodically (by freezing in an external mechanical 

refrigeration system), they offer low noise and require almost no maintenance. 

Other systems 

Cascade systems for trucks, combining a heat driven adsorption system and a vapour 

compression cycle are still under development. Other alternatives have also been considered 

in the road transport, but have not been pursued for numerous reasons. Adsorption and 

absorption systems are also being evaluated. 

6.5 Recovery, Reuse and Destructions of Refrigerants 

Handling of used refrigerant includes recovery, recycling, reclamation and destruction. All or 

any of these steps may be required by national legislation. In many countries, however, such 

requirements are absent. Although voluntary measures may sometimes be implemented, there 

will still be an opportunity for improvement in many countries as long as legal or monetary 

measures (incentives or tax to compensate for recycling, reclamation or destruction cost) will 

not be in place. 

6.6 Bank and Emission Data 

The estimates of approximate refrigerant banks and emissions in transport refrigeration are 

summarised in Tables 6-1 and 6-2 (rounded to 10). The data are based on estimates of the 

fleet size, refrigerant charge per system, refrigerant share in the fleet, and refrigerant 

emissions per system, which are presented in Tables 6-3 through 6-5. 

Except for marine vessels, the total refrigerant banks do not differ substantially from the data 

presented in the previous 2006 assessment report. Any difference is caused primarily by 

variation in partial source data (Tables 6-3 through 6-5). The banks reported for vessels are 

higher also due to the fact that the scope was expanded to smaller vessels down to 100 GT. 

The 2006 assessment considered merchant, naval and fishing vessels above 300 GT only. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 101

Table 6-1: Estimate of approximate refrigerant banks (t) 

 CFC HCFC HFC R-717 R-744 TOTAL 

Merchant, naval and 

fishing vessels 2500 21900 2730 20 110 27260 

Road vehicles 160 4860 14380 0 0 19400 

Railcars 20 210 80 0 0 310 

Interm. containers 0 210 4060 0 0 4270 

TOTAL 2680 27180 21250 20 110 51240 

Table 6-2: Estimate of approximate refrigerant emissions (t/y) 

 CFC HCFC HFC R-717 R-744 TOTAL 

Merchant, naval and 

fishing vessels 1000 6570 270 0 10 7850 

Road vehicles 50 970 1440 0 0 2460 

Railcars 0 40 10 0 0 50 

Interm. containers 0 40 200 0 0 240 

TOTAL 1050 7620 1920 0 10 10600 

Table 6-3: Estimate of fleet size and refrigerant charge 

Category System type Share Fleet Refr. charge (kg) 

Direct 90% 90000 200 

Merchant vessels 

Indirect 10% 10000 50 

Direct 100% 5000 200 

Naval vessels 

Indirect 0% 0 50 

Direct 70% 35000 200 

Fishing vessels 

Indirect 30% 15000 50 

Small trucks Belt driven 40% 1600000 2 

Large trucks Independent 30% 1200000 6 

Trailers 30% 1200000 7.5 

Railcars 100% 20000 15 

Interm. containers 100% 950000 4.5 

System type: Direct = direct expansion; Indirect = secondary loop
102 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 6-4: Estimate of approximate refrigerant share

Category System type CFC-11 CFC-12 HCFC-22 R-502 R-408A HFC-134a R-404A R-407C Merchant Direct 5% 5% 80% 7% 2% 1% vessels Indirect 80% 5% 5% 

Direct 90% 10% 

Naval vessels 

Indirect Direct 5% 5% 80% 6% 2% 1% 

Fishing vessels 

Indirect 80% 5% 5% 

Small trucks Belt driven 5% 85% 10% Large trucks Independent 20% 5% 5% 70% Trailers 20% 5% 5% 70% Railcars 5% 70% 5% 20% Interm. containers 5% 85% 10% System type: Direct = direct expansion; Indirect = secondary loop 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 6-5: Estimate of approximate refrigerant emissions in % of charge, per year, including leaks, total charge losses due 

and end of live losses.

Category System type CFC-11 CFC-12 HCFC-22 R-502 R-408A HFC-134a R-404A R-407C 

Direct 40% 40% 30% 10% 10% 10% 

Merchant vessels 

Indirect 30% 10% Direct 30% 10% 

Naval vessels 

Indirect Direct 40% 40% 30% 10% 10% 10% 

Fishing vessels 

Indirect 30% 10% 

Small trucks Belt driven 30% 10% 10% Large trucks Independent 20% 20% 20% 10% Trailers 20% 20% 20% 10% Railcars 30% 20% 10% 10% Interm. containers 20% 5% 5% System type: Direct = direct expansion; Indirect = secondary loop 
104 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

6.7 References 

/Agr10/ Agreement on the international carriage of perishable foodstuff and on the special 

equipment to be used for such carriage (ATP), United Nations, New York and Geneva, 

2010, http://www.unece.org/trans/main/wp11/atp.html 

/All00/ http://www.allbusiness.com/sales/customer-service-product-knowledge/677599-1.html, 

January 2010 

/Ana99/ Analyses of the vessels over 100 tons in the global fishing fleet, FAO Fisheries Circular 

No. 949, 1999, http://www.fao.org/docrep/005/X4360E/X4360E00.HTM 

/Cor08/ Corberan, J. M., Segurado, J., Colbourne, D. and J. Gonzalvez, Review of standards for the 

use of hydrocarbon refrigerants in A/C, heat pump and refrigeration equipment, 

International Journal of Refrigeration, 31(4), June 2008, 748-756 

/Equ07/ Equasis statistics – The world merchant fleet in 2007, http://www.equasis.org, August 

2010 

/FAO10/ Food and Agriculture Organization of the United Nations, http://www.fao.org/fishery/en, 

August 2010 

/Hil80/ Hill, R. P., Refrigerated railcars supply and demand, Speech presented to the AFFI-IARW 

Refrigerator Railcar Task Force, St Paul. Minn (1980) 

/IIR09/ IIR Newsletter, July 2009, International Institute of Refrigeration, Paris, France (referring 

to Fruit World International 1/2009) 

/ISO08/ ISO 1496-2:2008 Series 1 freight containers -- Specification and testing -- Part 2: Thermal 

containers, ISO 2008 

/Kue09/ http://www.kuehlwaggon.de, January 2010 

/Mar10/ Marine Pollution Convention, MARPOL 73/78, Annex VI, 

http://www.imo.org/Conventions/mainframe.asp?topic_id=148 

/Nav10/ http://www.navy.mil/navydata/navy_legacy_hr.asp?id=146, August 2010 

/Pal08/ Palm B., Hydrocarbons as refrigerants in small heat pump and refrigeration systems – A 

review, International Journal of Refrigeration, 31(4), June 2008, 552-563 

/Ref09/ http://www.refservice.ru/en/, January 2010 

/Rev09/ Review of maritime transport, United Nations Conference on Trade and Development, 

New York and Geneva, 2009, http://www.unctad.org 

/Sch09/ Schiffer V. – private communication, with reference to Gueterwagen-correspondenz Nr. 90 

– 3/2002, 2009 

/Sta07/ The state of world fisheries and aquaculture 2006, FAO 2007, 

http://www.fao.org/docrep/009/a0699e/a0699e00.HTM 

/Tec09/ Technical support for European action to reducing Greenhouse Gas Emissions from 

international maritime transport, December 2009, 

http://ec.europa.eu/environment/air/transport/ships.htm 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 105

Chapter 7 

__________________________________________________________ 

Air-to-Air Air Conditioners and Heat Pumps 

Chapter Lead Author 

Fred J. Keller 

Lead Authors or Co-Authors 

Daniel Colbourne 

Sukumar Devotta 

Reviewing Authors 

Radhey Agarwal 

Jim Crawford 

Martin Dieryckx 

Makoto Kaibara 

Ed McInerney 

Petter Nekså 

Horace A. Nelson 

Paulo Vodianitskaia 
106 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7 Air-to Air Air Conditioners and Heat Pumps 

7.1 Introduction 

On a global basis, air conditioners, including reversible air heating heat pumps (generally 

defined as “reversible heat pumps”) ranging in size from 2.0 kW to 420 kW comprise a vast 

majority of the air conditioning market (the majority are less than 35 kW). In the remainder 

of this chapter the term air conditioning will be used to apply to both air conditioners and airto-air heat pumps that directly heat air. This broad category is sometimes referred to as aircooled or unitary equipment /ASH08/. These systems cool and/or heat enclosed spaces 

ranging from single rooms to large exhibition halls. Essentially, most are electrically driven 

vapour-compression systems using hermetic rotary, reciprocating or scroll compressors for 

units with capacities up to about 100 kW, and single or multiple semi-hermetic reciprocating, 

scroll or screw compressors for units with capacities up to 400 kW. Air in the space is drawn 

over a coil containing evaporating refrigerant. Heat transfer occurs between the air and the 

circulating refrigerant. With heat pump systems, the role of the evaporator and condenser can 

be reversed to provide either heating or cooling. In the heating mode, air from the 

conditioned space passes over the same coil that now contains refrigerant undergoing 

condensation thereby transferring heat to the air. 

In 2008, an estimated 553 million HCFC-22 air conditioners were operating world-wide. 

Refrigerant charge quantities vary roughly proportional to capacity. These 553 million units 

represent an installed bank of approximately one million metric-tonnes of HCFC-22. 

Nearly all air conditioners manufactured prior to 2000 used HCFC-22. The transition away 

from HCFC-22 is nearly complete in developed countries. The phase-out of HCFC-22 in the 

manufacturing of new products in the EU was completed in 2004. The phase-out of HCFC-22 

was nearly completed (95%) in the manufacturing of new products in Japan in 2004, with the 

remainder occurring in 2009. The phase-out of HCFC-22 in new systems in North America 

was completed in 2009. However, it is important to note that technical options available at the 

time of the phase-out in these countries were environmentally focused on the protection of the 

ozone layer and not on the reduction of CO2 equivalent emissions. Some Non-Article 5 

countries have begun transitioning to non-ODP alternatives ahead of the Montreal Protocol 

commitment dates. Approximately 85% of the installed unit population currently uses HCFC22 and approximately 32% of the units produced globally in 2008 used non-ODP refrigerants. 

In 2006, HFC demand globally represented approximately 9% of the total refrigerant demand 

for these categories of products /Sab09/. 

7.2 Applications 

Air conditioners generally fall into four distinct categories, based primarily on 

capacity or application: small self-contained air conditioners (window-mounted and 

through-the-wall air conditioners); non-ducted split residential and commercial air 

conditioners; ducted, split residential air conditioners; and ducted commercial split 

and packaged air conditioners (commercial air cooled) /ASH07/, /ASH08/. In each of 

these categories, the term “air conditioner” includes systems that directly cool or heat 

the conditioned air. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 107

7.2.1 Small Self-Contained Air Conditioners 

Small Self-Contained (SSC) air conditioners are small capacity air conditioners in which all 

of the refrigeration system components are contained within a single package. These products 

have cooling capacities typically ranging from 1.0 kW to 10.5 kW. This category of products 

includes the following common configurations: 

• Window Mounted Room Air Conditioner, 

• Through-the Wall Air Conditioner 

• Portable Air Conditioner 2 

• Packaged Terminal Air Conditioner (PTAC). 

Small self-contained air conditioners are designed to heat or cool single spaces--such as 

bedrooms or small offices. Small self-contained air conditioners, because of their size and 

relatively low cost, have often been the first individual comfort electrically driven vapourcompression systems to appear in emerging air conditioning markets. However, global 

product shipment data indicates that duct-free, split type room air conditioners are being 

selected more frequently as the first comfort air conditioning option in most countries - 

resulting in a global decline in the demand for window mounted and through-the-wall air 

conditioners /JARN08/, /AHRI08/.

Small self-contained air conditioners range in capacity from less than 1.0 kW to 

approximately 10.5 kW (having an average size of 2.7 kW). These systems have average 

refrigerant charge levels of approximately 0.25 kg per kW of cooling capacity. All use hermetic 

rotary, reciprocating or scroll compressors, with the majority using hermitic rotary 

compressors. 

The majority of small self-contained air conditioners historically have used HCFC-22 

refrigerant. As non-ODP refrigerants have been applied to these products-the majority have 

used HFC blends. A small number units (approximately 100,000 portable units per year) are 

using hydrocarbons /UNEP05/. 

7.2.2 Non-ducted (or duct-free) Split Residential and Commercial Air Conditioners 

In many parts of the world, residential and light commercial air-conditioning is done with 

non-ducted split air conditioners. Non-ducted split air conditioners can be applied to 

commercial buildings, schools, apartments and free-standing residences. Non-ducted split air 

conditioners include a compressor/heat exchanger unit (condensing unit) installed outside the 

space to be cooled or heated. The outdoor unit is connected via refrigerant piping to one or 

more fan-coils located inside the conditioned space. Single splits often position the expansion 

device also within the condensing/outdoor unit. 

Non-ducted products can be sub-divided into two sub-categories: single split and multi-split. 

With single split products a single indoor fan coil unit is connected to an outdoor condensing 

unit. Small (less than 7 kW) non-ducted split air conditioners with a single indoor fan-coil are 

sometimes referred to as split type room air conditioners. In multi-split systems, a single 

outdoor condensing unit is connected to two or more indoor fan coils. 

 

2

 Portable air conditioners are a special class of room air conditioners that can be rolled from room to 

room. They exhaust their condenser air through a small flexible conduit, which can be placed in an 

open window. Some portable air conditioners use a separate outdoor condenser, which connects, to the 

indoor section with flexible refrigerant piping. 
108 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Reversible air conditioners (heat pumps) are gaining market acceptance in cold climates 

where they are used primarily for heating but also provide cooling during summer operation. 

These units are designed to provide high efficiency and capacity at low ambient temperatures; 

typically down to -30 °C. Reversible air conditioners reduce indirect CO2 emissions by 

providing an efficient and cost effective alternative to electric resistance and fossil fuel 

heating. Heat pumps designed for cold climates utilise one or more technologies to improve 

their low ambient performance. These technologies include multi-stage or variable speed 

compression, larger heat exchangers and enhanced control strategies. These products range 

from residential use up to VRF systems, which are used in large commercial applications. 

Variable Refrigerant Flow (VRF) systems are a sub-category of the multi-split non-ducted air 

conditioning systems. VRF systems are distinguished from regular multi-split systems by 

their ability to modulate the refrigerant flow in response to the system demand. VRF systems 

normally consist of a number of indoor air handling units connected to a single outdoor air 

conditioning unit. The outdoor air conditioning unit can adjust the refrigerant flow in 

response to the demand from each indoor unit. In some configurations, these systems can 

simultaneously heat and cool separate indoor spaces. The outdoor unit modulates the total 

refrigerant flow using various compressor capacity control methodologies. VRF systems have 

capacities ranging from 10 kW to over 130 kW. 

Non-ducted split air conditioners use hermetic rotary, scroll or reciprocating compressors. 

The vast majority of non-ducted air conditioners manufactured prior to 2000 used HCFC-22 

refrigerant. Non-ducted single split air conditioners have average HCFC-22 charge levels of 

approximately 0.25 to 0.30 kg per kW of cooling capacity. The average charge per kW 

increases as the operating efficiency of these systems increases due to the increased internal 

volume as the size of the heat exchangers is increased /ICF06/. Typical refrigerant charge 

levels for multi-split and VRF systems are 0.30 – 0.70 kg/kW of cooling. 

7.2.3 Ducted, Split Residential Air Conditioners 

Ducted, split residential air conditioners are typically used where central forced-air heating 

systems necessitate the installation of a duct system that supplies air to each room of a 

residence or small zones within commercial or institutional buildings. A condensing unit 

(compressor/heat exchanger), outside the conditioned space, supplies refrigerant to one or 

more indoor coils (heat exchangers) installed within the duct system or air handler. Air in the 

conditioned space is cooled or heated by passing over the coil and is distributed throughout 

the building by the duct system. Capacities range from 5 kW to 17.5 kW (average size 10.9 

kW) and each has an average HCFC-22 charge of 0.26 to 0.35 kg per kW of capacity. 

As the efficiency level of these products is increased, the average charge per kW typically 

increases unless design changes are made to reduce the product internal volume; such as 

smaller diameter heat exchanger tubing /ICF06/. In the United States, the minimum 

efficiency of residential air conditioners that can be manufactured was increased 30 percent in 

January 2006, from 10 SEER to 13 SEER. Products meeting the new efficiency standards 

have charge levels approximately 20 to 40% greater than the products designed to meet the 

prior minimum efficiency levels due to the increased heat exchanger surface added to meet 

the new minimum efficiency standard /ICF06/. However, considerable research is being 

conducted to reduce refrigerant charge levels /Pog08/, /Fer05/. Charge reduction technology 

will become increasingly important as the industry begins to transition to lower GWP 

alternatives, some of which are flammable. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 109

7.2.4 Ducted Commercial Split and Packaged Air Conditioners 

Ducted commercial air conditioners and heat pumps are manufactured in two forms: split 

system units which are matched with an indoor air handler and heat exchanger and single 

packaged units which contain an integral blower and heat exchanger section which is 

connected to the air distribution system of the commercial structure. 

The majority of ducted commercial packaged air conditioners and heat pumps are mounted on 

the roof of individual offices, shops or restaurants or outside the structure on the ground. 

Multiple units containing one or more compressors are often used to condition the enclosed 

space of low-rise shopping centres, shops, schools or other moderate size commercial 

structures. 

Large commercial structures such as hospitals, exhibition halls or high-rise structures 

generally utilise chillers to produce chilled water or brine which is used to cool and 

dehumidify air using liquid-to-air heat exchangers (Chapter 9). 

Table 7-1 summarises the typical physical and installation characteristics of each type of air 

conditioner. 

Table 7-1: Typical Configurations of Air Conditioner Type 

Type 

Primary 

Configuration 

System 

Layout 

Evaporator 

Location 

Condenser 

Location 

Capacity 

Range 

(kW) 

Charge 

Range 

(kg) 

Window Small Self-contained Selfcontained Inside Outside 1 – 10.5 0.3 – 3 

Portable Small Self-contained Selfcontained Inside Inside 1 – 10.5 0.3 – 3 

Through-the-Wall Small Self-contained Selfcontained Inside Outside 1 – 10.5 0.3 – 3 

Packaged terminal Small Self-contained Selfcontained Inside Outside 1 – 10.5 0.3 – 3 

Split (non-ducted) Non-ducted Split Remote Inside Outside 2 – 15 0.5 – 5 

Split (ducted) Ducted Split Remote Inside Outside 4 – 17.5 1 – 7 

Multi-split Non-ducted Split Remote Inside Outside 10 – 130 5 – 100 

Packaged Rooftop Ducted Commercial Selfcontained Outside Outside 7.0 – 350 5 – 100 

Ducted 

Commercial Split Ducted Commercial Remote Inside Outside 10.5 – 90 5 – 35 
110 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7.3 Current Use of HCFC-22 

Estimates of the installed base (number of units) and HCFC-22 inventory were made using 

computer models documented in prior assessments and other reports /Kel04/, /Clo04/, 

/Sab09/. Table 7-2 lists the estimated 2008 unit populations and HCFC-22 Refrigerant Banks 

for each of the product categories covered in this chapter.

Table 7-2: Estimated 2008 Unit Population and HCFC-22 Banks 

Product Category 

HCFC Units 

Operating3

(Million) 

HFC Units 

Operating 

(Million) 

Total Units 

Operating 

(Million) 

Estimated 

HCFC-22 

Bank4

(m-tonnes) 

Window-mounted and Through-the-Wall 

(Packaged Terminal) Air Conditioners4 116 16 132 84,000 

Non-ducted or Duct-free Split Residential 

and Commercial Air Conditioners 332 62 394 423,000 

Ducted, Split Residential Air conditioners 

and Heat Pumps 85 12 97 309,000 

Ducted Commercial Split and Packaged 

Air Conditioners 20 3 23 223,000 

Total 553 93 646 1,039,000 

7.3.1 Small Self-Contained Air Conditioners 

On a world-wide basis, an estimated 10.5 million HCFC-22 based window-mounted5

 and 

through-the-wall (packaged terminal) air conditioners were sold in 2008 containing on 

average for the entire population 0.75 kg of HCFC-22. 

 

With service lives over 10 years, it is estimated that more than 116 million HCFC-22 

window-mounted and through-the-wall air conditioners remain in operation globally (Table 7-

2). The total 2008 global bank of HCFC-22 in the installed population of window-mounted 

and through-the-wall air conditioners (including portable air conditioners) is estimated to be 

84,000 metric-tonnes. 

7.3.2 Non-ducted Split Air Conditioners 

An estimated 332 million HCFC-22 non-ducted split air conditioners were operating worldwide in 2008. Non-ducted split air conditioners, ranging in capacity from 2.0 kW to 20 kW 

(average size of 3.8kW). The total inventory of HCFC-22 in the installed population of ductfree split systems world-wide in 2008 has been estimated to be 423,000 metric-tonnes. 

 

3

 Unit population includes units manufactured with HCFC refrigerant. 

4

 HCFC-22 Bank does not include non-ODS refrigerants, HFC Bank not listed 

4

 Window mounted air conditioners are also sometimes installed through a penetration of the outside 

wall. Packaged Terminal Air Conditioners, PTAC, are similar to Window mounted air conditioners 

but typically contain some form of electric heat. PTACs are typically installed in hotel and motel 

rooms. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 111

7.3.3 Ducted, Split Residential Air Conditioners 

An estimated 85 million HCFC-22 ducted, split residential air conditioners were in service 

world-wide in 2008. The majority of these air conditioners are located in United States and 

Canada. The estimated bank of HCFC-22 in the installed population of ducted residential 

systems has been estimated to be 309,000 metric-tonnes. 

Approximately 56% of ducted, split residential air conditioners manufactured globally in 

2008 utilised non-ODS refrigerants. Approximately 12 million of the installed population of 

97 million (HCFC-22 and HFC) ducted, split residential air conditioners were manufactured 

with non-ODP refrigerants; such as R-407C and R-410A. 

7.3.4 Ducted Commercial Split and Packaged Air conditioner 

An estimated 20 million HCFC-22 air-cooled ducted commercial split and packaged air 

conditioners and heat pumps were operating world-wide in 2008. Ducted commercial air 

conditioners and heat pumps range in capacity from about 5 kW to as large as 420 kW. The 

estimated total worldwide bank of HCFC-22 in the installed base of these systems in 2008 has 

been estimated to be 223,000 metric-tonnes. Approximately 3 million of these 20 million aircooled ducted commercial units were manufactured with non-ODP refrigerants. 

7.3.5 HCFC-22 Bank 

On a mass basis in 2008, HCFC-22 accounted for 85% of the refrigerant bank for these 

product categories. Table 7-2 summarises the total estimated bank of HCFC-22 used in these 

product categories. 

Since the last assessment, there has been a significant increase in the number of new products 

in these categories, which utilise non-ODS refrigerants. In North America, HCFC-22 was 

phased out in new products at the end of 2009. Europe and Japan have also completed the 

shift to non-ODS refrigerants. 

The majority of Article 5 countries are still utilising HCFC-22 to produce these categories of 

products for their domestic markets. However, China and to a lesser extent India have been 

producing significant numbers of non-ODS products for export to non-Article 5 country 

markets. 

7.4 Options for New Equipment 

7.4.1 Methodology 

A survey of current product offerings indicates that the majority of non-ODS products 

available for the product categories covered in this section are using HFC blends as the 

predominate refrigerant, with a small number of units using hydrocarbon refrigerants 

(portable and small split system air conditioning units). While HFC-134a and R-744 are 

technically feasible options, there has been very limited commercialisation of air-cooled air 

conditioning products using HFC-134a or R-744. 
112 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

There are several factors that should be considered when selecting an alternative refrigerant 

for air conditioning applications. These are: 

• Safety, 

• Zero ODP, 

• Climate Change impact (reduced direct and indirect emissions), 

• Performance (Capacity and Efficiency) and, 

• Impact on Product Cost. 

The selection of a refrigerant for a given application should be a process of selecting an 

optimum solution considering each of the above criteria. Other than Zero ODP, the rest of 

the parameters will have to be traded-off against one another to arrive at the optimum 

solutions for each air conditioning application. In particular the carbon Impact will need to 

address both the “direct” and “indirect” contribution to the carbon footprint of the product 

over its life cycle. A number of approaches have been documented in the literature including: 

TEWI, LCCP, MCII and other methods /Kau08/, /UNE05/, /Riv08/, /Kin08/. 

Following is a summary of the most viable HCFC-22 replacement candidates for airconditioners. 

7.4.2 Single Component HFC Refrigerants 

Several single component HFC refrigerants have been investigated as replacements for 

HCFC-22. However, HFC-134a is the only single component HFC that has been 

commercially used in air conditioning systems. 

7.4.2.1 HFC-134a 

HFC-134a is the only single component HFC that has been commercially applied in this 

category of products. HFC-134a is not a drop-in replacement for HCFC-22. To achieve the 

same capacity as an HCFC-22 system, the compressor displacement must be increased 

approximately 40 percent to compensate for the lower volumetric refrigeration capacity of 

HFC-134a. Significant equipment redesign is necessary to achieve efficiency and capacity 

equivalent to HCFC-22 systems. These design changes include larger heat exchangers, larger 

diameter interconnecting refrigerant tubing, larger compressors and re-sized compressor 

motors. 

While HFC-134a is a potential HCFC-22 replacement in air-cooled systems, it has not seen 

broad use because manufacturers have been able to develop substantially lower cost aircooled air conditioning systems using HFC blends such as R-407C and R-410A. The 

predominant use of HFC-134a has been in water chillers and mobile air conditioning 

applications (Chapters 9 and 10 respectively). Therefore HFC-134a has seen limited 

application in air-cooled air conditioning applications. 

7.4.3 HFC Blends 

A number of HFC blends have emerged as replacements for HCFC-22 in air conditioning 

systems. Various compositions of HFC-32, HFC-125, and HFC-134a are being offered as 

non-ODS replacements for HCFC-22. The two most widely used HFC blends are R-407C and 

R-410A. R-407C and R-410A have GWPs near HCFC-22 (Table 2-1). 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 113

7.4.3.1 R-407C 

Performance tests with R-407C indicate that in properly designed air conditioners, this 

refrigerant will have capacities and efficiencies within ± 5% of equivalent HCFC-22 systems 

/Li00i/. As R-407C is zeotropic blend, temperature glide is significant. Counter flow design of 

heat exchangers can mitigate the negative impact of refrigerant glide. However, with 

reversible heat pumps it is difficult to employ counter flow heat exchanger designs because 

the refrigerant has opposite flow directions in the heating and cooling modes unless complex 

reversible refrigerant heat exchanger circuiting is employed. 

There are currently R-407C air conditioning products available in Europe, Japan and other 

parts of Asia. R-407C has also seen some limited usage in the North America, primarily in 

commercial applications. 

Since R-407C refrigerant requires only modest modifications to existing HCFC-22 systems, it 

has been used as a transitional refrigerant in equipment originally designed for HCFC-22. 

However, over time, many of the R-407C designs have been redesigned with R-410A to 

achieve size and cost reductions. 

7.3.3.2 R-410A 

R-410A is a binary blend that can replace HCFC-22 in new equipment production. This blend 

has a low temperature glide (near azeotropic). The normal boiling point is approximately 

10°C lower than HCFC-22, resulting in condensing pressures up to 4000 kPa which is 

approximately 50-60% higher than HCFC-22. R-410A also has favourable thermophysical 

properties, which enable the design of units, which are more compact than the HCFC-22 units 

they replace. 

R-410A air conditioners (up to 175 kW) are currently commercially available in the US, Asia 

and Europe. A significant portion of the duct-free products sold in Japan and Europe now use 

R-410A as the preferred refrigerant. Approximately 55% of the US Ducted Residential 

Market in 2008 used R-410A as the refrigerant. The US ducted residential market will 

predominately utilise R-410A as the HCFC-22 replacement refrigerant after 2009. 

System pressures with this blend are approximately 50 percent higher than with HCFC-22. 

System designers have addressed the higher operating pressures of R-410A through design 

changes such as thicker walls in compressor shells, pressure vessels (accumulators, receivers, 

filter driers etc.), heat exchangers and refrigerant tubing. 

7.4.4 Reduced GWP HFC Refrigerants and Blends 

7.4.4.1 HFC-32 

HFC-32 is one of the primary constituents of both R-410A and R-407C. HFC-32 is an A2L 

refrigerant having a GWP (675) approximately 70% less than that of R-410A, which makes it 

a lower GWP alternative to R-410A. HFC-32 exhibits slightly higher capacity and efficiency 

than R-410A. Because HFC-32 has an A2L flammability rating, the flammability would need 

to be mitigated in the design of the product by compliance with an applicable safety standard 

such as IEC 60335-2-40. R-410A systems should be able to be redesigned for HFC-32 with 

minor modifications. 

HFC-32 is not a drop in for HCFC-22 since its pressure is around 60% higher and its capacity 

is also approximately 60% greater than HCFC-22 /ASH09/. HCFC-22 systems would 

require significant redesign including: lower displacement compressors and other changes to 

the refrigeration system components to address the higher operating pressures; which will be 

nearly the same changes needed to redesign HCFC-22 equipment to use R-410A.
114 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7.4.4.2 HFC-152a 

HFC-152a has performance characteristics similar to HFC-134a. It has similar capacity and 

efficiency performance to that of HFC-134a. HFC-152a has a much lower GWP than HFC134a, R-410A or R-407C. HFC-152a has Class 2 flammability according to ISO 817, with a 

relatively high flame speed. The design of HFC-152a equipment should follow the 

requirements of relevant safety standards such as IEC 60335-2-40, which require limiting the 

refrigerant charge or under certain circumstances may necessitate the use of indirect systems. 

In addition, significant redesign of existing HCFC-22, R-410A or R-407C systems would be 

required to utilise HFC-152a. Changes would be required to address not only the 

flammability of HFC-152a but also its low volumetric refrigeration capacity, which is close to 

that of HFC-134a. The necessary system design changes are similar to those described for 

HFC-134a. 

It is unlikely that HFC-152a will be commercialised in air conditioning systems because its 

low density and flammability would result in significantly increased costs relative to an 

HCFC-22 system. 

7.4.4.3 HFC-161 

HFC-161 is also being evaluated as a replacement for HCFC-22 in air conditioning systems. 

HFC-161 is a flammable, low GWP alternative. Studies comparing HCFC-22 and HFC-161 

are just beginning to appear in the literature. Much of the current research is being conducted 

in China. As with all flammable refrigerants, HFC-161 would need to be applied using an 

appropriate safety standard such as IEC-60335-2-40. 

7.4.4.4 HFC-1234yf 

HFC-1234yf is an unsaturated HFC, which has zero ODP and very low GWP. This refrigerant 

has been proposed as an alternative to R-134a in automotive AC applications /Min08/. HFC1234yf is not a drop-in replacement for HCFC-22 for air-to-air air conditioning applications. 

Its thermodynamic performance is similar to R-134a. It has a lower volumetric refrigeration 

capacity than R-22, R-410A or R-407C and thus requires that compressors using this 

refrigerant have significantly larger displacements. Experimental studies indicate that HFC1234yf systems will be 40% larger and more costly than HCFC-22 systems /Fuj10/, /Hid10/. 

The design changes include larger displacement compressors, increased heat exchanger areas 

and larger diameter interconnecting tubing. These changes are similar to the changes 

described for HFC-134a in 7.5.2.1. HFC-1234yf has an A2L flammability rating and would 

need to be applied using an appropriate safety standard such as IEC-60336-2-40. 

Because HFC-1234yf is so similar to HFC-134a it will suffer from the same application cost 

issues discussed for HFC-134a. It is therefore unlikely that unitary air-conditioners using 

pure HFC-1234yf will be commercially viable. 

7.4.4.5 HFC-1234yf Blends 

Refrigerant manufacturers have proposed blending HFC-1234yf with other non-ODP 

refrigerants in order to more closely match the performance of the refrigerants currently being 

used in these products /Min08/, /Spa10/. Most of these blends contain one or more other 

HFC refrigerants and exhibit various levels of glide and in some cases flammability 

depending on the blend composition. These blends can be formulated to have performance 

characteristics similar to HCFC-22 or R-410A while having much lower GWPs. 

7.4.4.6 Lubricants for HFC Systems 

The naphthenic mineral-oil-based and alkyl benzene lubricants commonly used in HCFC-22 

systems are not miscible with HFC refrigerants. Considerable field experience has resulted in 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 115

the commercial availability of a number of synthetic lubricants for HFC systems. 

The two primary lubricants being used in HFC systems are: 

1. Polyolester (POE) Lubricants (Synthetic), and 

2. Polyvinylether Lubricants (PVE) (Synthetic). 

Of these, POE is the most widely used lubricant in HFC refrigerant applications. The 

selection of the lubricant to be used with a particular HFC is generally made by the 

compressor manufacturer whom makes the selection after extensive material compatibility 

and reliability testing.

7.4.5 Hydrocarbon Refrigerants 

Hydrocarbon systems are commercially available in a number of low charge air conditioning 

applications, such as small split, window and portable air conditioners. HC-290 is the most 

frequently used hydrocarbon refrigerant in air conditioning applications. When used to 

replace HCFC-22, HC-290 has performance characteristics which yield slightly better 

performance than HCFC-22 /Dev05i/, /ART01/. Compared to HFCs, hydrocarbon refrigerants 

have: reduced charge levels (approximately 0.05 - 0.15 kg/kW of cooling capacity), 

miscibility with mineral oils (synthetic lubricants are not required), reduced compressor 

discharge temperatures, and improved heat transfer due to favourable thermo-physical 

properties /Col99/. 

The factor that works against the safe application of HC-290 in air conditioning systems is its 

high flammability, which creates significant safety concerns in application, installation and 

field service. European and international standards limit the quantity of HC-290 that can be 

used in a system. IEC-60335-2-40 provides criteria used to determine the maximum 

allowable charge in a specific application. Section 7.4.7 provides a brief discussion of the 

methodology used by IEC-60335-2-40 along with examples of the charge limits for typical 

applications. Charge reduction technologies can reduce the refrigerant charge of hydrocarbon 

systems; which can increase the range of unit capacities which can use hydrocarbon or any 

flammable refrigerant. 

Risk analyses on the use of hydrocarbons in air conditioners suggest that provided the 

requirements of safety standards are met, the risk of ignition during normal operation is 

extremely low /Col04/. The situation leading to highest risk is sudden leaks, refrigerant 

handling, and servicing activities. Thus, installation and service practices must be modified to 

avoid exposing consumers and service technicians to the additional risks associated with 

highly flammable refrigerants. 

Another factor that must be considered with flammable refrigerants will be refrigerant reclaim and 

recovery requirements. Even though hydrocarbon refrigerants have minimal environmental 

impacts, there may still be a need to recover the refrigerant during servicing and at the end of the 

product’s life to protect those servicing or recycling the product. Current recovery and recycling 

practices depend largely upon national or regional regulations. For example, in Europe waste 

legislation implies that HCs must be recovered, whereas in many Article 5 countries, venting of 

HCs may be considered an acceptable option. 

The ultimate decision on whether hydrocarbon refrigerants are practical in air conditioning 

products will be determined by safety standards, local codes and whether the added costs of safety 

mitigation result in products more costly than those that can be developed using other non-ODS 

options. 
116 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7.4.5.1 Lubricants for Hydrocarbon Refrigerants 

A number of researchers and practical experience with hydrocarbon refrigerators confirm that 

hydrocarbon refrigerants can utilise mineral oil based lubricants /Col99ii/, /Bit04/. 

Compressor manufacturers’ catalogue data indicates that both mineral oil based and POE 

lubricants are being used in compressors designed for hydrocarbon applications. 

7.4.6 R-744 

R-744 offers a number of desirable properties as a refrigerant: ready availability, low-toxicity, 

low GWP and low cost. However, because of the low practical exposure limit of R-744, it 

needs to be applied using applicable safety standards. R-744 has a low critical point 

temperature which results in significant efficiency losses when it is applied at the typical 

indoor and outdoor air temperatures of air-to-air air conditioning applications; particularly in 

high ambient climates which could result in higher system costs /Elb08/, /Haf08/, /Joh08/. R744 air conditioning systems typically operate above the critical temperature of R-744 during 

heat rejection. Because of this, R-744 systems utilise gas coolers rather than condensers. 

R-744 air conditioners operating in warmer climates (design temperatures greater than 30 °C) 

are likely to have efficiencies 10-15% below best in class HFC based designs /ART03a/. 

However, a number of design enhancements can be made to improve their efficiency. The 

efficiency of R-744 systems can be improved through multi-stage compression, liquid 

injection, the addition of oil separators, the use of refrigerant ejectors or expanders, various 

inter-cycle heat exchangers, and cross-counter-flow heat exchangers, which take advantage of 

the favourable thermophysical properties of R-744 /Xie08/, /Wan08/, /Koy08/, Liu08/, 

/Peu08/, /Kas08/. The addition of efficiency enhancing components can improve the 

efficiency of R-744 systems, but will also increase the cost of R-744 systems. 

Gas cooler operating pressures for R-744 systems are high, typically as high as 14,000 kPa 

with a mean system pressure near 5,000 kPa /Ibr03/. The required hydrostatic burst strength 

of systems operating at these high pressures would have to be approximately 30,000 kPa 

/Bos08/. The higher operating pressures contribute to high specific cooling capacity, thus 

allowing the reduction of inner diameters of tubes and lower compressor displacement or 

swept volume. The smaller component diameters combined with significantly increased wall 

thickness are also necessary to address the high operating pressures of R-744. Design 

changes required to address the burst pressure requirements of R-744 systems will also result 

in manufacturing cost increases. The high cost of R-744 systems, unless resolved, is expected 

to substantially hinder the adoption of R-744 technology in air-to-air air conditioning 

applications. 

Air-cooled R-744 air conditioners have been introduced into the market in very limited 

quantities. R-744 VRF products have been introduced in the European market. Experimental 

results show that R-744 systems may compete in energy efficiency with high efficiency R410A systems for moderate climates in both cooling and heating mode; however, 

improvements are needed to significantly improve the capacity, efficiency and reduce the 

peak electrical power requirements during the cooling mode in high ambient conditions 

/Jak07/. 

7.4.6.1 Lubricants for R-744 Systems 

The solubility of R-744 in lubricant is relatively high at the crankcase operating pressures of 

R-744 compressors /Cas01/. The knowledge base of information on lubricant compatibility in 

R-744 refrigeration systems is expanding as more researchers conduct studies of R-744 

compressors /Hub02/, /Li00ii/, /You03/, /Mul08/. Some of the lubricants being considered 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 117

for R-744 systems are POEs, PAO, and naphthenic mineral oil or alkyl benzene lubricants 

/You03/, /See06/. It is very likely that an oil separator will be needed in R-744 systems 

because of the large detrimental impact oil circulation has on the heat transfer performance of 

R-744 /Mue08/. 

7.4.7 Flammability Considerations 

When designing systems using flammable refrigerants the designer will need to meet the 

requirements of applicable safety standards. An example of such a standard is IEC-60335-2-

40 /IEC06/. This standard specifies construction requirements, charge limits, ventilation 

requirements and requirements for secondary refrigerant circuits. 

This standard uses the lower flammability limit, LFL, and the specifics of the application 

(location of equipment, the ventilation of the unit, the volume of the installed space and 

whether or not the space containing the unit is ventilated) to determine the maximum charge 

level, ventilation requirements and whether or not a secondary refrigerant circuit is required. 

Table 7.3 presents an example of the maximum allowable refrigerant charge determined by 

IEC-60335-3-40 for both a ventilated and unventilated space with all or part of the system 

installed in the indoor space. The maximum charge for other refrigerants and application 

conditions can be easily calculated using the equations in Annex GG of the standard. 

Table 7-3: Example of Maximum Refrigerant Charge per IEC-60335-2-40, (kg) 

Refrigerant Ventilated Space Unventilated Space6

R-290 1.0 0.3 

R-32 8.0 4.0 

R-161 2.0 0.7 

7.4.8 Not-in-Kind Alternative Technologies 

In past assessments, a number of potential new technologies were presented as options that 

could have a positive impact on the phase-out of ODS refrigerants. Some of the technologies 

presented in prior assessments were: absorption, desiccant cooling systems, Stirling systems, 

thermoelectric and number of other thermodynamic cycles. However, a search of the 

literature published since the prior assessment has continued to confirm that most of these 

technologies have not progressed much closer to commercial viability for air-cooled air 

conditioning applications than they were at the time of the 1990 assessment and three 

subsequent assessments. While these alternative cycles are feasible they have thus far not 

been proven to be economically viable. Therefore, it is unlikely that they will significantly 

penetrate these markets, other than potential niche applications (such as localities where 

electricity is unavailable), during the next decade. Alternative cycle technologies will 

therefore have a minimal impact on the HCFC-22 phase-out in both developed and 

developing countries. 

However there are some mature proven alternative technologies, which can provide non-ODP 

options for some regions and applications. For example, Evaporative Cooling technology 

could provide a very low cost and energy efficient alternative or supplement to vapour 

compression refrigeration in hot arid climates /ASH07/.

 

6

 Assumes 15 m2 floor area with unit mounted 1.8 m above the floor 
118 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7.5 Options for Existing Equipment 

After the HCFC phase-out occurs in Non-Article 5 or Article 5 countries there will still be a 

need to service the installed population of products until the end of their useful lives. 

Servicing of these products can fall into three categories: 

1. Service field repair 

2. Drop-in Refrigerant field repair 

3. Retrofit field repair 

All three repair methods will be important for Article 5 countries because systems are often 

repaired several times in order to extend their useful lives. There are a large number of Small 

Volume Consuming (SVC) countries, which import rather than manufacture air-conditioners. 

Therefore most of the HCFC consumption in these countries is used to service the installed 

base of air-conditioners. In these countries, HCFC consumption can be reduced by the use of 

service refrigerants or by retrofitting existing equipment to non-ODP refrigerants. A third 

less desirable option because of cost, would be to replace the existing equipment before the 

end of its useful life. The availability of service refrigerants and retrofit options will be very 

important for these SVC countries during this period. 

In Non-Article 5 countries, unit replacement is more common because the costs associated 

with performing a major repair or retrofit can often be greater than the cost to replace the 

product. 

Service field repair is any repair that can follow normal service practices using new, recycled 

or reclaimed refrigerant. 

Drop-in refrigerant field repair replaces the HCFC-22 with one of the available service 

blends, without changing the lubricant used in the original equipment. Refrigerants meeting 

these requirements are sometimes referred to as Service Fluids or Blends. In cases where 

the drop-in refrigerant results in a significantly lower capacity or efficiency than HCFC-22, 

the retrofit approach will be more appropriate. 

Retrofit field repair techniques range from simply changing the refrigerant, lubricant and filter 

dryer (if required) to more extensive modifications which could include the replacement of 

the compressor, refrigerant, lubricant, dryer, expansion device, and purging and flushing the 

system to remove all residual lubricant from the system. Any refrigerant and lubricant 

removed from the system should be disposed of in an environmentally responsible manner, in 

accordance with applicable environmental regulations. Retrofit field repair can be 

substantially more costly than service or drop-in repairs or even unit replacement. 

Refrigerants that require lubricant changes or system component changes are often described 

as retrofit refrigerants. Retrofit refrigerants will probably not be cost effective if either the 

compressor or heat exchangers must be replaced. 

In the case of retrofit or drop-in replacement in HCFC-22 systems, the global warming 

impact of the replacement refrigerant should also be given consideration. 

7.5.1 Service Blend Refrigerants 

There are several Service Blends currently being introduced to replace HCFC-22 for 

servicing. These refrigerants are primarily being promoted as a drop-in and retrofit

refrigerants for HCFC-22 in air conditioning applications. They generally combine two or 

more HFC refrigerants with a small amount of hydrocarbon refrigerant. The hydrocarbon 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 119

refrigerant is added to the blend to enable the refrigerant to work with the naphthenic mineraloil-based and alkyl benzene lubricants used in nearly all HCFC-22 air conditioning systems. 

The Service Blend refrigerants attempt to mimic the performance of HCFC-22. However, 

these refrigerants generally do not perform as well as HCFC-22; having either lower capacity, 

efficiency or both in drop-in applications. A sampling of the many commercially available 

HCFC-22 Drop In Refrigerant blends are: R-422D, R-438A, R-424A and R-417A (Chapter 

2). Information on the application of these blends can be obtained from their manufacturers. 

7.5.2 Retrofit Refrigerants 

R-407C has been demonstrated to be an acceptable retrofit refrigerant for HCFC-22 systems. 

It has seen widespread use as a retrofit refrigerant in some locations with some loss in 

capacity and efficiency. Its performance is very similar to HCFC-22 but it does require that 

the existing naphthenic mineral oil or alkyl benzene synthetic oil lubricant be replaced. R407C compatible filter driers should be installed on HCFC-22 systems retrofitted to R-407C. 

The disadvantage of using high glide blends is the need to remove and replace the entire 

charge during servicing to avoid substantial composition shift. However, because R-407C has 

moderated glide, laboratory and field experience with R-407C systems indicates R-407C 

systems can be serviced without replacing the entire refrigerant charge with minimal impact 

on performance. 

7.5.3 Anticipated Market Impact of Drop-in and Retrofit Refrigerants 

The need for, and market impact of, drop-in and retrofit refrigerants will largely be 

determined by the size of the installed population of HCFC-22 products, HCFC phase-out 

schedule, allowed service tail, the availability of service HCFC-22 and the recovery and 

reclaim practices in place leading up to the phase-out. The term “service tail” is used to 

describe the time between when a refrigerant has been phased out for use in new equipment 

and the date at which the refrigerant may no longer be produced. It is anticipated that service 

(reclaimed or recycled HCFC-22), retrofit and drop-in refrigerants will be important for 

Article 5 countries, because of the limited capital available to manufacture new non-ODS 

systems and the longer useful lifetimes which are the result of the common practice of 

servicing rather than replacing a product when major failures occur. 

The installed population of air conditioners and heat pumps has an average service life in nonArticle 5 countries of 15 to 20 years. The average useful life of these products in Article 5 

countries may be longer. Therefore, implementing recovery and reclaim programs coupled 

with the availability of drop-in and retrofit refrigerants could help reduce the demand for 

HCFC-22. 

7.5.4 Hydrocarbons as Conversion/Drop-in Refrigerants 

It has been reported that HC-290, HC-1270 and HC-290/HC-170 blends have been used as 

conversion/drop-in replacements for HCFC-22 in some locations. While these refrigerants 

may provide capacity and efficiency close to HCFC-22, this practice creates a significant 

safety concern because of the high flammability of these refrigerants. If hydrocarbons are 

being considered; all relevant safety standards and codes-of-practice should be strictly 

followed. The GTZ Handbook for HC Safety is one source of information on the utilisation 

of HC refrigerants /GTZ10/. 
120 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7.6 High Ambient Considerations 

The objective of this section is to summarise the performance of the various HCFC-22 options 

for high ambient air conditioning applications (above 40 °C). The governing thermodynamic 

properties and principles result in a declining capacity and efficiency for all refrigerants as the 

heat-rejection (refrigerant condensing) temperature increases, including HCFC-22. However, 

some of the HCFC-22 replacements exhibit greater degradation in capacity and efficiency 

than HCFC-22 under high ambient conditions. Currently, the most widely applied 

replacements for HCFC-22 in unitary air conditioning applications are HFC blends, primarily 

R-410A and R-407C. Hydrocarbons are also being used in some low refrigerant-charge 

applications. This material summarises the information in: Decision XIX/8: Alternatives to 

HCFCs at High Ambient Temperatures /UNE10/. 

R-410A and R-407C both have lower critical temperatures than R-22. This occurs because 

HFC-125 (a component of both R-407C and R-410A) has a comparatively low critical point 

temperature of 66.0°C (150 °F). The critical point temperature is important because 

refrigerants having a low critical point temperature will exhibit a steeper decline in capacity 

with increased ambient (outdoor) temperatures than refrigerants having higher critical point 

temperatures. This steeper decline in capacity is of particular importance in geographic 

regions, which have cooling design temperatures approaching the critical point temperature of 

the refrigerant. 

7.6.1 R-410A in High Ambient Applications 

R-410A systems have been demonstrated to operate acceptably at ambient temperatures up to 

52 °C. The performance (capacity and efficiency) of R-410A air-conditioners falls off more 

rapidly than HCFC-22 systems at high ambient temperatures (above 40 °C) as shown in Table 

7.4 /UNE10/. 

Table 7-4: High Ambient Performance Relative to HCFC-22, % 

Refrigerant Condensing Temperature (°C) 

40 50 60 65 

HCFC-22 100 100 100 100 

HFC-32 100 100 99 98 

HFC-134a 100 99 97 96 

HC-290 100 98 96 95 

R-407C 100 97 94 92 

R-410A 100 97 93 90 

HC-600a 100 100 99 97 

Units designed for equal capacity at 40 °C 

The optimum selection of compressor, airflow, condenser design and expansion device can 

reduce the performance losses at high ambient temperatures /Bat04/. Even with optimised 

designs, when applying R-410A systems that will operate a significant number of hours at 

high ambient temperatures, the system designer should take into consideration the reduced 

high ambient capacity when sizing the equipment. For cases where the base capacity of the 

unit would need to be increased to meet the building load at extreme ambient temperatures the 

following rule of thumb should be sufficient in estimating the cost impact. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 121

7.6.2 HC-290 in High Ambient Applications 

HC-290 has performance characteristics similar to HCFC-22. The characteristics are close 

enough that the current products that employ HCFC-22 could be re-engineered to employ 

HC-290. HC-290 has successfully been demonstrated as an HCFC-22 replacement in low 

charge, room and portable air-conditioners applications /Dev09a/. HC-290 shows a 5 percent 

reduction in capacity at 65 °C, Table 7-4. 

IEC standard 60335-2-40 has established the criteria for determining the maximum charge 

limit for highly flammable refrigerant applications. This standard also establishes mechanical 

and electrical design requirements and maximum charge limitations for flammable 

refrigerants. Safely and cost effectively applying hydrocarbons to larger unitary systems will 

be a significant technical challenge. 

7.6.3 R-407C in High Ambient Applications 

R-407C systems will typically perform in nearly the same way as HCFC-22 systems at typical 

ambient temperatures. At ambient temperatures above 40°C, R-407C systems show less 

degradation of capacity and efficiency than R-410A systems. However, an R-407C system 

will still exhibit a capacity approximately 8% less than an HCFC-22 system at a condensing 

temperature of 65 °C (Table 7-4). Since R-407C refrigerant requires only modest 

modifications to existing HCFC-22 systems, it has also been used as a transitional refrigerant 

in equipment originally designed for HCFC-22. 

There are currently R-407C air conditioning products widely available in Europe, Japan and 

other parts of Asia. 

7.6.4 HFC-32 in High Ambient Applications 

HFC-32 is being considered as an alternative to R-410A. HFC-32 will have higher efficiency 

and capacity at high ambient temperatures. HFC-32 will have a capacity approximately 2 

percent less than an HCFC-22 system at 65 °C condensing temperature (Table 7-4). HFC-32 

is likely to become a longer-term replacement for R-410A. It has a GWP approximately 32% 

that of R-410A and exhibits much better high ambient performance than R-410A. However, it 

has an A2L flammability, which will need to be addressed in the design and application of the 

product using appropriate safety standards. The design changes required to convert from R410A to HFC-32 should be straightforward. While HFC-32 systems are currently under 

development, none are currently available in the market. 

7.6.5 HFC-134a and HC-600a in High Ambient Applications 

HFC-134a and HC-600a would seem attractive from the point of view that they have similar 

performance to HCFC-22 at high ambient temperatures. However, both of these refrigerants 

are low-pressure refrigerants. Therefore, extensive redesign of the base system components 

would be required in order to achieve the same capacity and efficiency of the HCFC-22 

system. Design changes would include larger displacement compressors, increased heat 

exchanger areas and increases in the piping sizes used in heat exchangers and inter-connecting 

tubing. All of these changes would lead to substantial increases in the product cost. In 

addition, additional design changes would be required with HC-600a to address the high 

flammability of this refrigerant. Therefore, HFC-134a and HC-600a are not considered the 

most viable options to replace HCFC-22 in unitary air-conditioning applications. 
122 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

7.6.6 R-744 in High Ambient Applications 

R-744 offers a number of desirable properties as a refrigerant: readily available, low GWP 

and low cost. These desirable characteristics are offset by the fact that R-744 has a very low 

critical temperature (31°C) and will operate above critical point conditions in most airconditioning applications. Operation at these conditions results in a significant degradation in 

both capacity and COP at high ambient temperatures. 

These losses can be partially offset by the addition of internal cycle heat exchangers and 

expanders or ejectors. However, R-744 systems are not expected to provide a cost effective 

alternative to HCFC-22 or HFC refrigerants when being applied in high temperature regions 

(> 40°C). 

7.6.7 HFC Replacements for High Ambient Applications 

Alternatives to HFC refrigerants for air-conditioning applications are in the early stages of 

development. A number of new refrigerants are being investigated to replace R-407C and R410A, including HFC-1234yf and blends of other HFC refrigerants with HFC-1234yf. While 

refrigerant manufacturers are believed to be working to qualify other chemicals or blends that 

might be new, their development has not progressed to the point where they are available to 

unitary equipment manufacturers for evaluation and equipment development. Therefore, it is 

premature to recommend alternatives to R-410A or R-407C at this early stage of the 

development other than HC-290, which may be applicable in low charge applications when 

appropriate safety and application requirements are considered. 

7.7 References 

/AHRI08/ 2008 Unitary Air Conditioner Shipment Data, Air Conditioning Heating and Refrigeration 

Institute, Arlington Va. , 2008. 

/ART01/ Assessment of the Commercial Implications of ASHRAE A3 Flammable Refrigerants in Air 

Conditioning and Refrigeration, Final Report; ARTI 21-CR/610-50025-01; Air 

Conditioning and Refrigeration Technology Institute (ARTI), Arlington, VA, USA 

September 2001. 

/ART03a/ Evaluation Of The Performance Potential Of CO2 As A Refrigerant In Air-To-Air Air 

Conditioners And Heat Pumps: System Modelling And Analysis, Final Report; ARTI21CR/610-10030; Air Conditioning and Refrigeration Technology Institute (ARTI), 

Arlington, VA, USA December 2003. 

/ART03b/ CO2 Compressor Expander Analysis, Final Report; ARTI-21CR/611-10060-01; Air 

Conditioning and Refrigeration Technology Institute (ARTI), Arlington, VA, USA March 

2003. 

/ASH07/ HVAC Applications Handbook; American Society of Heating, Refrigeration and AirConditioning Engineers (ASHRAE); Atlanta Georgia, USA, 2007. 

/ASH08/ HVAC Systems and Equipment; American Society of Heating, Refrigeration and AirConditioning Engineers (ASHRAE); Atlanta Georgia, USA, 2008. 

/ASH09/ Handbook of Fundamentals; American Society of Heating, Refrigeration and AirConditioning Engineers (ASHRAE); Atlanta Georgia, USA, 2009. 

/Bae08/ Baek, Changhyun and Lee, Eungchan et al; Experimental Study on the Heating 

Performance of a CO2 Heat Pump With Gas Injection; International Refrigeration and Air 

Conditioning Conference at Purdue, July 14-17, 2008 

/Bit04/ Bitzer International, “Refrigerant Report, 13th Addition A-501-13, September 2004 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 123

/Bos08/ Bosco, R. and Weber, G.; Challenges on the Development of A CO2 Compressor Focusing 

on Structural Strength and Reliability; 8th IIR Gustav Lorentzen Conference on Natural 

Working Fluids, Copenhagen, Denmark 7-10 September 2008 

/Cas01/ Casini, Dorin, CO2 Compressors and Equipment Use and Availability, IX Convegno 

Europeo – Politecnico di Milano, Italy, 29-30 Giugno 2001 

/Clo04/ Clodic, D., Palandre, L., Kuijpers, L., Estimation of the world-wide fleets of refrigerating 

and air-conditioning equipment in order to determine forecasts of refrigerant emissions, Ecole 

des Mines de Paris, Center for Energy Studies, Paris, France, 2003. 

/Col99/ Colbourne, Daniel, Practical Application of Hydrocarbon Refrigerants: Production Cost 

and Operational Performance, 20th IIR Congress of Refrigeration, IIR/IIF, Sydney, 1999. 

/Col00/ Colbourne, Daniel, Assessment of the Performance of Hydrocarbon Refrigerants, IIF-IIR 

Commission B1, B2, E1 and E2, Purdue, West Lafayette, IN USA, 2000. 

/Col04/ Colbourne, D., Suen, K. O. (2004) Appraising the Flammability Hazards of Hydrocarbon 

Refrigerants using Quantitative Risk Assessment Model. Part II: Model evaluation and 

analysis, International Journal of Refrigeration, Vol. 27, pp. 784 – 793. 

/Cox08/ Cox, N. and Mazur, V. et al; New High Pressure Low-GWP Azeotropic and Near 

Azeotropic Refrigeration Blends; International Refrigeration and Air Conditioning 

Conference at Purdue, July 14-17, 2008. 

/Dev05i/ Devotta, S., Padalkar, A.S. and Sane, N. K., Performance assessment of HC-290 as a 

drop-in substitute to HCFC-22 in a window air conditioner”, International Journal of 

Refrigeration, 28, 594-604, 2005. 

/Elb08/ Elbel, Stefan and Hrnjak, Predrag; Ejector Refrigeration: An Overview of Historical and 

Present. Developments with and Emphasis on Air-Conditioning Applications; International 

Refrigeration and Air Conditioning Conference at Purdue, July 14-17, 2008. 

/Fer05/ Fernado, P., Lunquist, P.; Refrigeration systems with minimized refrigerant charge: system 

design and performance; Journal Proceedings of the Institution of Mechanical Engineers, 

Part E: Journal of Process Mechanical Engineering , Issue Volume 219, Number 2 / 2005. 

/Fuj10/ Fujitaka, Akira and Shimizu, Tsutomu et al; Application of Low Global Warming Potential 

Refrigerants for Room Air Conditioner, 2010 International Symposium on Next Generation 

Air Conditioning and Refrigeration Technology, Tokyo, Japan, 2010. 

/GTZ10/ Guidelines for the safe use of hydrocarbon refrigerants, (2010) GTZ Proklima, Eschborn, 

Germany, http://www.gtz.de/en/themen/umwelt-infrastruktur/28719.htm

/Haf08/ Hafnet, A. and Garski, D. J. et al; Air Reversing R-744 Air Conditioning System ; 8th IIR 

Gustav Lorentzen Conference on Natural Working Fluids, Copenhagen, Denmark 7-10 

September 2008. 

/Hid10/ Hara, Hideki and Ohno, Masao et al; Experimental Study of Low GWP Refrigerants for 

Room Air-Conditioners, 2010 International Symposium on Next Generation Air 

Conditioning and Refrigeration Technology, Tokyo, Japan, 2010. 

/Hub02/ Hubacher, B., Groll, E., Hoffinger, C., Performance Measurements of a Semi-Hermetic 

Carbon Dioxide Compressor, Ninth International Refrigeration and Air Conditioning 

Conference, Purdue University, West Lafayette, IN. USA, July 2002. 

/Ibr03/ Ibrahim, A.G., Fleming, J.S. , Performance Assessment of a Transcritical CO2 Heat Pump 

using a Reciprocating Compressor, International Congress of Refrigeration, Washington, 

D.C., August 2003. 

/ICF06/ ICF International, Projected Servicing Needs in the U.S. Air-Conditioning and 

Refrigeration Sector, Prepared for the U.S. EPA, September 2006, Washington DC. 

/IEC06/ International Electrotechnical Commission, International Standard 60335-2-40, 

Household and similar electrical appliances – Safety, Part 2-40; Particular Requirements 

for electrical heat pumps, air-conditioners and dehumidifiers, Geneva, Switzerland, 2006. 
124 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

/JARN08/ Japanese Air Conditioning, Heating and Refrigeration News; World Air Conditioning 

Market, August 2008 

/JAK07/ Jakobsen, A., Skiple, T., Nekså, P., Wachenfeldt, B. and Skaugen, G. (2007): Development 

of a reversible CO2 residential air conditioning system, 22nd Int. Congress of Refrigeration, 

Bejing, August 2007. 

/Joh08/ Johansen, Bent; Applications and Experience with Natural Refrigerants Carbon Dioxide/ 

CO2 and Hydrocarbon R-1270; ; 8th IIR Gustav Lorentzen Conference on Natural Working 

Fluids, Copenhagen, Denmark 7-10 September 2008. 

/Kas08/ Kasayer, E. Bou Lawz and Clodic, D.; ID Analysis of CO2 Sub-Cooled/Supercritical 

Ejector Refrigeration Cycle: Experimental Results; 8th IIR Gustav Lorentzen Conference 

on Natural Working Fluids, Copenhagen, Denmark 7-10 September 2008. 

/Kau08/ Kaufeld, Michael and Harnisch, M. J. et al; Environmental Impact of Various Alternative 

Supermarket Refrigeration Systems; 8th IIR Gustav Lorentzen Conference on Natural 

Working Fluids, Copenhagen, Denmark 7-10 September 2008. 

/Kel97/ F. Keller, Unit Population and Refrigerant Inventory Predictions Using Product Life 

Models, Special Report to TOC, November 1997. 

/Kel04/ Keller, Fred J. , Modeling of Air Conditioning HCFC Emissions Using Product Life 

Models, Post IPCC-TEAP 3LAM Workshop, Organized by JICOP and Ozone Layer 

Protection Policy Offices Office (METI), Toranomon Pastoral, Tokyo, Japan, July 1, 2004. 

/Kin08/ Kinab, Elias; Seasonal Coefficient of Performance of Heat Pumps; International 

Refrigeration and Air Conditioning Conference at Purdue, July 14-17, 2008. 

/Koy08/ Koyma, S. and Xue, J. et al; An Experimental Study of the Cooling Performace of a CO2

Cycle with an Internal Heat Exchanger; 8th IIR Gustav Lorentzen Conference on Natural 

Working Fluids, Copenhagen, Denmark 7-10 September 2008. 

/Li00i/ Li, H., and Rajewski, T. E., Experimental Study of Lubrication Candidates for the CO2

Refrigeration System, Proc. of the 4th IIR–Gustav Lorentzen Conference on Natural 

Working Fluids, Purdue University, West Lafayette, IN, July 25-28, pp. 438-445, 2000. 

/Li00ii/ Li, D et al; Performance of a Carbon Dioxide-Based Environmental Control Unit (ECU) 

for the US Army; Eighth International Refrigeration Conference, Purdue, West Lafayette, 

IN USA, 25-28 July 2000. 

/Liu08/ Liu, F. and Groll, E.; Investigation of a Two-Phase Flow Ejector in a Transcritical CO2 Air 

Conditioning System; 8th IIR Gustav Lorentzen Conference on Natural Working Fluids, 

Copenhagen, Denmark 7-10 September 2008. 

/Min08/ Minor, Barbara and Spatz, Mark; HFO-1234yf Low GWP Refrigerant Update; 

International Refrigeration and Air Conditioning Conference at Purdue, July 14-17, 2008. 

/Mul08/ Muller, R. and Eggers, R.; Heat Transfer Characteristics of CO2-Oil Mixtures; 8th IIR 

Gustav Lorentzen Conference on Natural Working Fluids, Copenhagen, Denmark 7-10 

September 2008 

/Nek01/ Neksa, Peter, Prospective for the Use of CO2 in Refrigeration and Heat Pump Systems, 

Trondheim, 23-25 March 2001. 

/Peu08/ Peuker, Jennifer and Hrnjak, Predag; Investigation to Improve Efficiency of Transcritical 

R744 Two-Stage Vapor Compression Systems; International Refrigeration and Air 

Conditioning Conference at Purdue, July 14-17, 2008. 

/Pog08/ Poggia, Macchi-Tejedaa, Leducqa, Bontemps; Refrigerant charge in refrigerating systems 

and strategies of charge reduction , International Journal of Refrigeration, Volume 31, 

Issue 3, May 2008, Pages 353-370. 

/Riv08/ Riviere, P. et al; Preparatory study on the environmental performance of residential room 

conditioning appliances (airco and ventilation) - Technical Analysis Of Best Available 

Technology; Contract TREN/D1/40-2005/LOT10/S07.5660, July 2008. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 125

/Sab09/ Sabine, S, Barrault, S. and Clodic, D.; Stationary Air Conditioning Assumptions and 

Results – Working Document, Ecole des Mines Paris, 28 November 2009. 

/See06/ Seeton, Chris, Lubricants for CO2, USNC/11R Short Course, Purdue University, West 

Lafayette, IN, USA, 15-16 July 2006. 

/Spa10/ Spatz, M. and Motta, S.Y. et al; Low Global Warming Alternative Refrigerants for 

Stationary AC&R Applications; 2010 International Symposium on Next-generation Air 

Conditioning and Refrigeration Technology, 17 – 19 February 2010, Tokyo, Japan. 

/UNE05/ IPCC and TEAP, Special Report on Safeguarding the Ozone Layer and the Global Climate 

System, Issues Related to Hydrofluorocarbons and Perfluorocarbons, Intergovernmental 

Panel on Climate Change Technology and Economic Assessment Panel, 2005. 

/UNE10/ Decision XIX/8: Alternatives to HCFCs at High Ambient Temperatures, UNEP 

Refrigerant Technical Options Committee special report, April 2010. 

/Wan08/ Wang, Hongli and Ma, Yitai et al; Performance Comparison of Transcritical CO2 Single 

Compression and Two Stage Compression Cycle with Intercooler; 8th IIR Gustav 

Lorentzen Conference on Natural Working Fluids, Copenhagen, Denmark 7-10 September 

2008. 

/Xie08/ Yingbai, Xie, and Sun, G. et al; Thermodynamic Analysis of CO2 Supercritical Two-Stage 

Compression Refrigeration Cycle; International Refrigeration and Air Conditioning 

Conference at Purdue, July 14-17, 2008. 

/You03/ Youbi-Idrissi, M., Bonjour, J., Terrier, M., Solubility of CO2 in a Synthetic Oil, 21st IIR 

International Congress of Refrigeration, Washington D.C., USA, August 17-22, 2003. 

2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 127

Chapter 8 ________________________________________________________________________

Heat Pumps 

Chapter Lead Author 

Makoto Kaibara 

Co-Authors 

Martin Dieryckx 

Petter Nekså 

Contributors 

Fred J. Keller 

James M. Calm 

Daniel Colbourne 

Michael Kauffeld 

Alexander C. Pachai 

Kenneth E. Hickman 

Roger Nordman 
128 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

8 Water heating heat pumps 

8.1 Introduction 

Heat pumps are able to upgrade (“pump”) heat from a lower temperature to a useful higher 

temperature level. The heat is used for space heating, service (including domestic) water 

heating, and manufacturing process heating. The heat sources are generally renewable energy 

sources, such as ambient heat, water or ground-source heat. Most commonly, the source is air-

, water-, or ground heat. The sink can be air or water. This chapter covers only systems where 

water is the sink. The products for industrial process heating are covered in chapter 5 

“Industrial systems”. Air-to-air heat pumps are the most widely used heat pumps. Their 

construction and refrigerant use is similar to air conditioners; therefore they are covered in 

chapter 7 “Air-to-air air conditioners and heat pumps”. 

The difference between the temperature of source and sink (called “lift” or “head”) sets the 

basic pressure rise condition the compressor must meet. The compression energy is a fraction 

of the total useful energy delivered. The power consumption of the heat pumps is dictated by 

the heating capacity required of the heat pumps, the lift, and compressor/driver efficiency. 

The heated water pumping power, and fan power must be included to determine the power 

consumption of the total heat pump system. In general, heat pump systems will be less 

efficient under higher lift condition. 

Heat pumps are in many applications an alternative to fossil fuel gas or oil combustion 

boilers, often resulting in a significant reduction in CO2 emission and primary energy 

consumption. 

Air-to-water heat pumps have experienced significant growth in Japan, Europe, China, and 

Australia during the last five years. In Japan and Europe, this significant growth has been 

enhanced by government incentive policies encouraging the development and sale of products 

utilising renewable energy sources /JRA09a/. According to estimates from a leading trade 

publication in Japan, more than 1 million air-to-water heat pumps were sold world-wide in 

2008 /JARN09/. This total can be broken down as 500k in Japan, 300k in Europe, 190k in 

China, and 10k in USA and Australia /JARN09/. The USA also uses large quantities of waterloop heat pumps in commercial and institutional buildings, with heat addition and removal to 

the loop as needed seasonally and even diurnally. 

8.2 Types of Heat Pumps 

Heat pumps are classified by heat source (air, water, and ground) and heat sink (air, water), 

resulting in the following naming of heat pumps in table 8-1 used in this chapter. 

Table8-1 Heat pump classification

Heat source (direct expansion or indirect expansion system) 

Air Water Ground 

Air Air to air Water to air Ground to air 

Water heater 

Space heating 

Heat 

sink Water 

Combined 

Air to water Water to water Ground to water 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 129

Air-source heat pumps are equipped with air-to-refrigerant evaporator coils and fans to obtain 

heat from the ambient air. Water-source heat pumps are equipped with water-to-refrigerant 

evaporators and a water circulation pump to obtain the heat from a water source. Ground 

source heat pumps are generally equipped with a brine-to-refrigerant evaporator and brine to 

ground tubes combined with a circulation pump or, refrigerant-to-ground evaporator tubes to 

obtain heat from the ground. The tubes in the ground are installed horizontally one to a few 

meters below ground level or installed in a vertical drilled hole, typically 50-150 m deep. 

Most heat pumps are driven by electric motors, but gas engine drives are used in fewer cases. 

It is also possible to classify heat pumps by types depending on the usage: 

1) Heat pump water heaters (HPWH) 

2) Space heating heat pumps 

3) Combined water and space heating heat pumps 

8.2.1 Heat Pump Water Heaters (HPWH) 

Heat pump water heater (HPWH) are a category of heat pumps designed to heat domestic and 

other service hot water to temperatures between 55 and 90 °C. These operating temperatures 

must be considered when selecting the refrigerant. 

A HPWH basically consists of a water storage tank and a heat pump water heating unit and in 

some designs an additional heat exchanger. In the heat pump unit, water supplied from the 

storage tank or directly from the city water supply is heated by the condenser or, for transcritical cycles using R-744 the gas cooler of the refrigerant circuit and then returned to the 

storage tank. Stored hot water is supplied to each tapping point, in response to the demand. 

The basic components of the heat pump unit are; a compressor driven by an electric motor, a 

condenser or a gas cooler for heating water, an evaporator to absorb heat from the heat source, 

refrigerant, a refrigerant expansion device, and a control unit. Heat pump units that use R-744 

as a refrigerant typically use an additional internal heat exchanger, and in some cases, an 

ejector or expander to improve energy efficiency /Cal84, Koy08/. 

In order to obtain high water temperatures at low outdoor ambient temperatures, air to water 

heat pump systems can utilise a cascade refrigerating system with two different refrigerants. 

8.2.2 Space Heating Heat Pumps 

A space heating heat pump is optimised for comfort heating. Comfort heating heats the room 

by heating water for distribution to an air handling unit, radiator or under floor panel. The 

required water temperature depend on the types of emitter, low temperature application 

ranging from 25 to 35°C for under floor heating, for moderate temperature application such as 

air handling units around 45 °C, for high temperature application such as radiant heating 55 to 

60 °C, and for very high temperature application, as high as 65 to 80 °C, such as for the fossil 

fuel boiler replacement market. The required warm water temperature affects the selection of 

refrigerant. Heat pump systems are more efficient at lower sink temperatures, but each 

product must fulfil the required operating temperature. 

A space heating heat pump using warm water for distribution generally consists of a heat 

pump unit and often an additional heat exchanger unit and a water storage tank. Several 

different configurations are used. In the heat pump unit, the basic components of a heat pump 

space heating system are a compressor driven by an electric motor, condenser or gas cooler 

for warming up water, an evaporator, refrigerant, a refrigerant expansion device, and a control 

unit. 
130 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Ground and water source heat pumps are also used for space heating, but they represent a 

small segment of the total heat pump market. 

8.2.3 Combined Space and Hot Water Heat Pumps 

Combined water heating and space heating heat pumps have two functions, supplying hot tap 

water and providing space heating. Several configurations of combined space and water 

heating heat pumps exist to optimise the seasonal energy efficiency. In most configurations a 

water storage tank is used to store the domestic hot water and to also act as a short heat buffer 

for the space heating function. 

8.2.4 Capacity Ranges of Water and Space Heating Heat Pumps 

Table 8-2 lists the heating capacity range offered by single units of each type of heat pumps. 

Table 8-2: Heat Pump Capacity Ranges

Heat pump type Capacity Range (kW) 

Heat pump water heater 1.5 – 50

Space heating heat pump 4 – 400

Combined water and space heating heat pump 6 – 45 

8.3 Heat Pump Implications and Trends 

8.3.1 Trends of Heat Pumps Replacing From Gas or Fuel Burning System 

Most of the space heating systems and water heating systems globally use fossil fuels. Since 

fossil fuel burning systems generate CO2 during combustion, they contribute to global 

warming. Heat pumps also contribute to global warming but in a different way. Heat pumps 

transfer heat from lower temperature source to a high temperature sink. The contribution to 

global warming is only related to CO2 emissions in the generation of the electricity to drive 

the compressor and possible direct contributions due to refrigerant emissions. Therefore, the 

heat pumps energy efficiency is the primary environmental consideration for heat pumps. 

Efficient heat pumps can reduce global warming impact compared with fossil fuel burning 

systems significantly. The reduction depends on the efficiency level of the heat pump and the 

carbon emission per kWh of the electricity generation. 

The tendency of decarbonisation of electricity strengthens this positive effect year by year. 

Also the efficiency levels of heat pumps are improving year by year. However, heat pumps 

tend to be higher in cost than fossil fuel systems because they employ complicated refrigerant 

circuits, larger heat exchangers and other special features. The majority of purchasers have 

not yet accepted the significantly higher first costs of heat pumps as a means to reduce 

running costs, compared to lower first cost fossil fuel based space and water heating systems. 

However, government support programmes in Europe and Japan to promote heat pump 

systems have resulted in rapid growth of heat pump system sales in recent years. 

In Europe around 40 % of all primary energy is used in buildings from which nearly 75% is 

used for space and domestic hot water heating. Energy use accounts for nearly 80% of all CO2 

equivalent emissions /EHPA09/. In Europe, heat pumps are expected as the best available 

technology for space heating. It contributes to reduction in both primary energy use and CO2 

emissions. Some believe that there will be a rapid increase of heat pump applications in 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 131

Europe. In Sweden more than 75 % of all new building heating systems now are installing 

heat pumps /EHPA09/. 

As a result of recent technology developments, Air source heat pumps have become the most 

popular heat pump type in Europe. They have experienced strong growth over the last several 

years because of their economic benefits and energy efficiency benefits. The positive 

environmental aspects and potential market growth of heat pumps must be taken into account 

when refrigerant options and limitations are considered. Compared to 2008 figures the heat 

pump market in Europe is expected to double by 2015 and to grow by 7 times by 2030. The 

total installed equipment in Europe will, compared to 2008, become 3 times in 2015 and 16 

times in 2030 /EHPA09/.

Predicated on the new efficiency standards and analyses used in development of these 

national requirements, estimated HPWH shipments in the USA are 10,000 units per year in 

2010, 260,000 units per year by 2015, and - though somewhat speculative - 270,000 or more 

units per year by 2020 /Amr10/. 

8.3.2 CO2 Heat Pump Water Heaters 

Heat pump water heater using R-744 refrigerant have become very popular in recent years in 

Japan under the trade name “Eco-cute” and are also introduced in Europe. These R-744 heat 

pump water heaters were launched in 2001. From 2001 till October 2009 a total of 2.0 million 

units have been sold in Japan, with annual sales of 500,000 units in 2008. Target for 2020 is 

10 million units /JRA09a, JRA09b/ 

This growth is the result of; its relative high efficiency for heating water up to 90 °C (without 

supplementary heater), a very low night tariff for electricity, and government incentives, in 

the capacity range up to 12 kW. The Japanese have a culture of daily hot bathing. This results 

in a significant demand for hot water. To satisfy this large demand within a limited time (at 

late night when electrical tariffs are lower) and with limited storage tank capacity, a water 

temperature of approximately 90 °C is required. R-744 as refrigerant performs very well at 

conditions requiring a large temperature difference of the water to be heated. Therefore, R744 is ideally suited for small tank storage type heat pump water heaters. The “Eco-Cute” 

performance has been improved by using existing and new technologies such as counter flow 

heat exchanger to achieve high temperatures by utilising the large temperature glide of R-744, 

variable speed compressor, internal heat exchanger and ejector to improve efficiency /Koy08/. 

Recently, an evaluation method for defining the annual performance factor of heat pump 

water heaters has been established in Japan. This method considers the typical Japanese life 

style usage of hot tap water. 

HPWHs for commercial use with R-744 are produced by several manufacturers inside and 

outside Japan. 

8.4 Current Refrigerant Options for Water and Space Heating Heat Pumps 

Dedicated heat pump water heaters (HPWHs) - uniquely for domestic and other service water 

heating - were first introduced commercially in the 1950’s in the USA, but production was 

halted. Interest re-kindled in the mid-1970s after the first OPEC Oil Embargo, and there were 

at least 17 manufacturers by the early 1980s with more than 23,000 units in use in the USA 

/Cal84/. Most employed HCFC-22 as the refrigerant. 

Interest in the technology again dwindled primarily due to higher equipment costs, though 

studies showed good performance and energy savings averaging 48% /Cal84, Dob84/. 
132 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Commercial interest in the USA resumed in late 2009 and 2010. Three major and several 

additional manufacturers began marketing newer, more efficient integral designs in 2010. 

These new products use either HFC-134a or R-410A as the refrigerant, but the split between 

them is uncertain /Amr10/. 

Space heating heat pumps have been developed (mainly in Europe) as a replacement for fossil 

fuel burning systems or direct resistive space heating systems. Space heating heat pumps are 

designed to supply water at different temperatures depending on the type of indoor heat, 

emitter such as radiators for high or moderate temperature water, fan coils for moderate

temperature water or under floor heating for low temperature water. 

High and moderate temperature space heating heat pumps were offered with HCFC-22 as 

refrigerant. With the implementation of the Montreal Protocol, HFC blends R-410A and R407C have been used as alternatives for HCFC-22, mainly in Europe. 

8.4.1 HCFC-22 

HCFC-22 is an ODS which has a high global warming potential. HCFC-22 has favourable 

thermodynamic properties and high efficiency in these applications. Therefore, HCFC-22 is 

being used for high and moderate temperature water and space heating heat pumps in the A5 

countries mainly in China. 

8.4.2 HFC-134a and HFC blends R-407C and R-410A 

HFC-134a and HFC blends R-407C and R-410A are non-ODS and have GWPs in the same 

range as HCFC-22. These refrigerants are being used in high to low temperature water and 

space heating heat pumps, in countries where HCFC-22 consumption reduction started in 

advance of the Montreal Protocol. These refrigerants are used mainly in Europe. R-134a and 

R-410A also are used in Japan, Canada and USA and to a lesser extent in Mexico and the 

Caribbean countries. R-407C has been used to mainly replace HCFC-22 in existing product 

designs because minimal design changes are required. R-410A has been used primarily for 

new products, because design changes are necessary to address its higher operating pressures 

and higher density and to take advantage of its higher performance. 

Recently, cascade heat pumps using HFC-134a and R-410A have been commercialised in 

high temperature combined space and hot water heating heat pumps in Europe. These heat 

pumps have a relatively good performance and can operate without auxiliary resistive heaters. 

The heat pump can supply water at temperatures approaching 80 oC. 

8.4.3 Hydrocarbons 

Hydrocarbons HC-290 and HC-600a are non-ODS refrigerant with a very low GWP, but 

these refrigerants have high flammability classified as an A3 refrigerant under ASHRAE 

standard 34. HC-290 has refrigerant properties similar to those of HCFC-22. Today, HC-290 

and HC-600a are used in a limited number of high and moderate temperature space heating 

heat pumps in Europe. Until 2004 almost half of the heat pumps sold in the EU used HC-290. 

Use in Europe has declined due to introduction of the Pressure Equipment Directive /Pal08/. 

8.4.4 R-744 (Carbon Dioxide) 

R-744 is a non-ODS refrigerant with a very low GWP. Development of R-744 heat pumps 

started around 1990 /Nek98/. R-744 heat pump water heaters were introduced to the market in 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 133

Japan in 2001, with heat pumps for heating of bath or sanitary water as the main application. 

Space heating heat pumps that operate at lower water temperatures in combination with hot 

water heating have also been developed, but the numbers sold are less. 

R-744 operates at very high pressures; approximately 5 times higher than HCFC-22 and 3.5 

times higher than HFC-410A. This is an advantage enabling more compact system designs. 

The low critical temperature of R-744 results in trans-critical operation. R-744 refrigerant has 

been used primarily in storage type heat pump water heater applications. It can achieve high 

efficiency when heating water to a high temperature (90 °C). However, R-744 has not been 

used much in space heating because space heating heat pumps do not need to operate at such 

high temperatures. Compared to HFC refrigerants many design modifications are required to 

get equivalent performance with R-744 for space heating alone /Nek10/. 

The market for heat pump water heaters in Japan is steady growing at a rate of about 10 to 

20% per year. This is because of the high efficiency when requiring high temperature water, 

such as 90 oC. 

Support from government enhancing programs is also an important element. Recently, some 

water heating heat pumps using R-744 also have been introduced in the European market. 

Although the current market for space heating heat pumps for commercial buildings with 

combined radiator and air heating systems is limited, R-744 is consider to be a promising 

refrigerant /Nek02/. 

8.4.5 R-717 (Ammonia) 

R-717 is a non-ODS refrigerant and has a very low GWP, but it has higher toxicity and lower 

flammability characteristics. R-717 is used mainly for large capacity systems. It has also been 

used in a small number of reversible heat pumps. 

8.4.6 Refrigerant Charge Levels 

Table 8-3 below shows approximate charge levels for HPWHs and space heating heat pumps 

with several typical refrigerants. 

Charge levels may vary over a range of values for each refrigerant and type of heat pump 

depending on capacity levels, target energy efficiency levels, etc. 

Table 8-3: HPWH and space heating heat pumps refrigerants and average charge levels

Refrigerant kg/kW 

HCFC-22 0.30 

HFC-134a 0.40 

HFC blends R-410A and R-407C 0.30 

Hydrocarbons 0.15 

R-744 0.15 

8.5 Future Refrigerant Options for New Heat Pumps 

When selecting alternative refrigerants, both the direct and indirect climate impacts must be 

considered. The direct effects to be taken into account are ozone depletion and global 

warming performance resulting from refrigerant emissions. Indirect climate effects that must 

be taken into account are the carbon emissions resulting from the generation of the electric 
134 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

power required to operate the equipment. These should be evaluated over its lifetime. For heat 

pumps, the reduction in emission resulting from replacing fossil fuel burning may be the most 

important factor regarding greenhouse gas emissions. The Life-Cycle Climate Performance 

(LCCP) method can be applied /UNE05/ to evaluate the combined effects. Also properties 

such as toxicity, flammability, thermo-physical properties, chemical stability, aquatic toxicity 

of decomposition product, pressure and density must be taken into account. 

Future refrigerant options for new heat pumps include current options R-410A, HFC-134a, 

HC-290, HC-600a, R-744, R-717, as well as HFC-32 and new refrigerants. 

Studies of new low-GWP fluorochemicals (notably unsaturated HFCs – see Chapter 2 

“Refrigerants”) in heat pumps are ongoing, notably in several European countries, Japan, and 

the USA. Similar studies are underway to evaluate use or broader use of R-744 and 

hydrocarbons as refrigerants in several types of heat pumps, though actual product 

development and commercialization are limited to Europe and Japan at present. 

8.5.1 HFC-134a and HFC Blends R-407C and R-410A 

Most new heat pump products are using the refrigerant R-410A because it results in more 

compact and efficient systems when they are optimised. The transition away from HCFC-22 

to R-407C and R-410A in heat pumps is well underway in developed countries. The transition 

is just beginning in Article 5 countries, which have later phase-out dates for HCFC-22. But, 

still much HCFC-22 refrigerant is used in these countries. 

Recently air to water split cascade systems are put on the market using R410A for the low 

temperature and HFC-134a for the high temperature circuit. They guarantee high seasonal 

COP for colder climates even at high water sink temperatures, while keeping the required 

heating capacity without auxiliary resistive heaters. They are most useful for combined space 

and hot water heating to replace existing boiler systems. 

8.5.2 HFC-32 

HFC-32 is a non-ODS refrigerant. It is one of the primary constituents of R-410A. It has a 

lower GWP than HCFC-22 or R-410A, approximately one third of HCFC-22 and R-410A. In 

addition, HFC-32 has a higher operating efficiency than HCFC-22 and R-410A /Shi01/. It has 

saturation pressures slightly higher than R-410A which is approximately 60% higher than 

HCFC-22. The system refrigerant charge can be up to 43% less than for R22 and 37% less 

than for R410A while the energy efficiency is the same or higher/YAJ01/. It has low 

flammability with a low burning velocity. 

8.5.3 HFC-1234yf and Other Low-GWP HFC Blends 

HFC-1234yf is a non-ODS and is similar in thermophysical properties to HFC-134a, but has a 

very low GWP of about 4 /Min08/. For water heating and space heating heat pumps using 

HCFC-22, R-410A, R-407C, significant design changes would be required to optimise for 

HFC-1234yf. Some of the required changes include; larger displacement compressors, larger 

interconnecting and heat exchanger tubing and additional heat exchanger surface to offset 

lower heat transfer. The heat transfer is expected to be lower than for R-410A systems 

because of its lower saturation pressure. The relatively higher pressure drop in the refrigerant 

pipes and heat exchanger will result in poor efficiency at the high temperatures typical for 

heat pump water heaters. HFC-1234yf has a low flammability with a low burning velocity. 

A number of other unsaturated chemicals are being identified in the patent literature as 

possible low-GWP refrigerants for heat pumps. Blends with R-32 or R-125 may make it 

possible to approach the properties of HCFC-22 or R-410A, but it results in a higher GWP 

than pure HFC-1234yf. As sample supply of these refrigerants is very limited, it is too early 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 135

to judge whether any of these chemicals will be commercialised and will show acceptable 

performance in heat pump systems. 

8.5.4 R-744 (Carbon Dioxide) 

In the past, R-744 was not used in water and space heating heat pumps because of its high 

pressure characteristics /Fer08/. After water heating heat pumps were introduced in Japan in 

2001, their market in Japan has experienced a steady growth of around 30% per year with 

help from a government enhancement programme /JRA09a/. R-744 as refrigerant enables 

high efficiency domestic water heating up to temperatures as high as 90 oC without use of an 

auxiliary resistive heater. R-744 may give a high performance when it is used with low 

temperature sources and high temperature sinks with a certain temperature difference between 

inlet and outlet water temperature /Ste08/. This makes it well suited for use in storage type 

heat pump water heaters in which low temperature inlet water is heated to a high temperature 

for thermal storage of domestic hot water. Continued growth of market is expected in Japan. 

In addition, it is expected that these products may experience market success in other 

countries. 

To obtain high efficiency for domestic space heating application is challenging if the 

difference between the high and low water temperature of the heat sink is low. System 

designs enabling a low water return temperature are then required /Nek10/. However, 

recently, R-744 heat pumps have been developed in Europe for use in cold climates if 

combined with very high temperature radiator type space heating are used. For commercial 

buildings with combined radiator and air heating systems, R-744 is a very promising 

refrigerant /Nek02/. This also holds for new low energy buildings where the domestic hot 

water demand is large compared to the space heating requirement. It is not known what level 

of market penetration R-744 space heating heat pumps will experience. The ultimate market 

acceptance will be determined by the system economics and its Life Cycle Climate 

Performance. 

8.5.5 Hydrocarbons 

At present HC-290 is sold in a relative limited number of low charge level heat pump water 

heater installations in Europe. While, for hydronic systems, with ventilated enclosures 

configuration, larger refrigerant charges are allowed. In these applications larger capacity 

systems can be used with hydrocarbons. 

8.5.6 R-717 (Ammonia) 

Ammonia is used mainly for large capacity systems. It has also been used in a small number 

of reversible heat pumps. It is not expected to be used in small capacity water and space 

heating heat pumps, because of the cost that makes it not viable as well the possibility to 

make so small systems due to the unavailability of hermetic compressor for ammonia and 

incompatibility with copper. 

8.6 References 

/Amr10/ Amrane, K, unpublished private communication, Air-Conditioning, Heating, and 

Refrigeration Institute (AHRI), Arlington, VA, USA, July 2010 

/Cal84/ Calm, J. M., “Heat Pump Water Heaters” in Heat Pump Research and Applications, report 

EM-3797, Electric Power Research Institute (EPRI), Palo Alto, CA, USA, pp. 14.1-14.9, 

November 1984 
136 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

/Dob84/ Dobyns, J. E. and M. H. Blatt, “Hea/Yaj01/ R. Yajima, K. Kita, S. Taira, N. Domyo R32 as 

a solution for energy conservation and low emission , IIR 2000 Purdue t Pump Water 

Heaters”, report EM-3582 Electric Power Research Institute (EPRI), Palo Alto, CA, USA, 

May 1984 

/EHPA09/ Forsen M and T. Nowak, European Heat Pump Statistics Outlook, European Heat Pump 

Association, Belgium, 2009

/Fer08/ N. FERNANDEZ, Y. HWANG*, R. RADERMACHER Center for Environmental Energy 

Engineering, Department of Mechanical Engineering, University of Maryland 

PERFORMANCE OF CO2 HEAT PUMP WATER HEATERS ,8th IIR Gustav Lorentzen 

Conference on Natural Working Fluids September 7-10, 2008 

/JARN09/ Japanese Air Conditioning, Heating and Refrigeration News; World Heat Pumps and Key

Components, Special Edition August 25, 2009

/JRA09a/ The Japan Refrigeration and Air Conditioning Industry Association; Statistics of heat 

pump water heater in 2008, June, 2009 

/JRA09b/ The Japan Refrigeration and Air Conditioning Industry Association; Statistics of heat pump 

water heater..., November, 2009 

/Min08/ Minor B. H. and T. J. Leck, DuPont Fluoroproducts, U.S.A. Low GWP Refrigerant 

Technology Update, The International Symposium on New Refrigerants and 

Environmental Technology (Kobe, Japan), November 20-21 2008

/Nek98/ Nekså, P., Rekstad, H., Zakeri, G.R. and Schiefloe, P.A.: CO2 – heat pump water heater:

characteristics, system design and experimental results, Int. J. Refrig. Vol. 21, No. 3, 

pp.172-179, 1998 

/Nek02/ Nekså, P: CO2 Heat Pumps, International Journal of Refrigeration, Vol 25, Issue 4, June 

2002, p 421-427, 2002 

/Nek10/ Nekså, P., Walnum, H. and Hafner A.: A refrigerant from the past with prospects of being

one of the main refrigerants in the future, 9th IIR Gustav Lorentzen Conference 2010, 

Sydney, April 12-14, ISBN 978-2-913149-74-8, ISSN 0151-1637, 2010 

/Koy08/ S. KOYAMA, J. XUE, N. TAKATA, K. KUWAHARA Interdisciplinary Graduate School 

of Engineering Sciences, Kyushu University, An Experimental Study On The Cooling

Performance Of A CO2 Cycle With An Internal Heat Exchanger, 8th IIR Gustav Lorentzen 

Conference on Natural Working Fluids September 7-10, 2008

/Pal08/ Palm, B. (2008) Hydrocarbons as refrigerants in small heat pump and refrigeration 

systems-a review, Int. J. of Refrigeration 31, 2008 

/Shi01/ T Shigeharu, Y Ryuzaburo, K Shigeru, (2001) The Performance Evaluation of Room Air

Conditioner using R32 In the Case of Cooling and Heating Mode, Trans JSRAE, Vol.18; 

No.3.

/Ste08/ J. Stene, SINTEF Energy Research, Department of Energy Processes, Norway, CO2 Heat

Pump System for Space Heating and Hot Water Heating in Low-Energy Houses and

Passive Houses, 8th IIR Gustav Lorentzen Conference on Natural Working Fluids 

September 7-10, 2008 

/UNE05/ IPCC and TEAP, Special Report on Safeguarding the Ozone Layer and the Global Climate

System, Issues Related to Hydrofluorocarbons and Perfluorocarbons, Intergovernmental 

Panel on Climate Change Technology and Economic Assessment Panel, 2005.

/Yaj01/ R. Yajima, K. Kita, S. Taira, N. Domyo R32 as a solution for energy conservation and low 

emission , IIR 2000 Purdue 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 137

Chapter 9 

__________________________________________________________ 

Chillers

Chapter Lead Author 

Kenneth E. Hickman 

Co-Authors 

James M. Calm 

Guangming Chen 

Jim Crawford 

Dennis Dorman 

Alexander C. Pachai 

Andy Pearson 

Contributors 

Daniel Colbourne 

Petter Nekså 

Akira Ohtsuki 
138 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

9 Chillers 

9.1 Function of Chillers 

Comfort air conditioning in large commercial buildings and building complexes (including 

hotels, offices, hospitals, universities, and other central systems) is commonly provided by 

chillers. Chillers cool water or other heat transfer fluid (such as a water-antifreeze mixture) 

that is pumped through heat exchangers in air handlers or fan-coil units for cooling and 

dehumidifying the air. Chillers also are used for process cooling in commercial and industrial 

facilities such as data processing and communication centers, electronics fabrication, 

precision machining, and moulding. District cooling is another application that provides air 

conditioning to multiple buildings through a large chilled water distribution system, as 

opposed to air conditioning each building with separate systems. Chiller operation is driven 

by cooling requirements but provision for heat recovery may be included. 

9.2 Types of Chillers 

Two types of chillers are available – mechanical vapour-compression chillers and absorption 

chillers. 

9.2.1 Mechanical Vapour-Compression Chillers 

The principal components of a vapour-compression chiller are one or more compressors 

driven by electric motors (or less commonly, engines or turbines using open drive 

compressors), a liquid cooler (evaporator), a condenser, a refrigerant, a lubrication system, a 

refrigerant expansion and flow control device, a power handling device (commonly a starter 

or variable speed electronic drive), and a control and protection unit. The complete chiller 

usually is factory assembled and tested; no connection between refrigerant-containing parts is 

required on site by the installer except for very large chillers which may be shipped as 

multiple assemblies. Installation is accomplished by connection to water, power, and control 

systems. 

Vapour-compression chillers are identified by the type of compressor they employ; 

centrifugal or positive displacement compressors. The positive displacement category 

includes reciprocating piston, screw, and scroll compressors. Chillers can be further divided 

according to their condenser heat exchanger type, the most common being water-cooled or 

air-cooled. Less common are evaporatively-cooled condensers and dry coolers. 

Water-cooled chillers generally employ cooling towers for heat rejection from the system. In 

some cases, the condenser cooling water may come from surface water such as lakes, rivers, 

or groundwater. Dry coolers function like cooling towers but water is not employed on the 

external heat transfer surfaces. Air-cooled chillers are factory-equipped with refrigerant-to-air 

condenser coils and fans to reject heat to the atmosphere. 

For evaporatively-cooled condensers, heat from the condensing refrigerant is rejected to the 

air in a coil that is continually wetted on the outside by a recirculating water system. Air is 

directed over the coil causing a small portion of the water to evaporate to help cool the coil. 

There is no circulation of water from the condenser to the chiller. Most of these chillers are 

supplied without the condenser which is added in the field. This requires refrigerant piping at 

the installation site. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 139

The different methods of heat rejection can be associated with differences in initial cost, 

installation cost, maintenance requirements, and the saturated condensing temperature created 

in the refrigerant circuit. The condensing temperature is driven by weather – the dry bulb 

and/or wet bulb temperatures. The difference between saturated condensing temperature and 

the saturated evaporator temperature (called “lift” or “head”) sets the basic pressure rise 

condition the compressor must meet. The power consumption of the chiller is dictated by the 

cooling capacity required of the chiller, the lift imposed by the weather (or heat recovery 

condition), and compressor/driver efficiency. The chilled water pumping power, cooling 

tower water pumping power (water cooled chillers), and fan power (in the tower or for air 

cooled chillers) must be included to determine the power consumption of the total chiller 

system. 

In general, water-cooled and evaporatively-cooled systems can be more efficient than aircooled systems under many operating conditions due to the lower condensing temperatures 

involved. The selection of water-cooled, air-cooled, dry coolers, or evaporatively-cooled 

chillers for a particular application varies with regional conditions, power costs and demand 

costs, owner preferences, maintenance requirements, and project budget. 

9.2.1.1 Centrifugal compressor chillers 

Centrifugal compressors with one, two, and three compression stages are employed in chillers 

according to engineering selection and manufacturer preferences. Two and three stage 

compressors allow addition of an economiser with interstage cooling to improve energy 

efficiency. Other features that can be used to enhance chiller operation over a range of cooling 

loads and ambient conditions are inlet guide vanes, variable-speed drives, variable-geometry 

diffuser passages, lubricant-free magnetic bearings, optimal staging (loading and control) of 

multiple chillers, and off-peak energy storage. The application of variable-speed drives lowers 

annualised energy consumption but can decrease full-load efficiency because of inverter and 

drive losses. 

Centrifugal compressors most commonly are used in water cooled systems, especially those 

with capacities exceeding 1 MW (300 RT). Air cooled centrifugal chillers are less common. 

They generally require at least two compressor stages because of the higher lift. 

Centrifugal chillers typically use flooded or pool-boiler type evaporators with the refrigerant 

on the shell side of the tubes although some designs use falling film sprayed evaporators. 

Chilled water is confined to the inside of the tubes, facilitating periodic cleaning of the water 

tubes to eliminate efficiency-reducing mineral build-up. Refrigerant-in-tube evaporators with 

chilled water on the shell side, sometimes called DX evaporators, are not practical in the large 

chiller systems that use centrifugal compressors. Accordingly, there is a limit on refrigerant 

selection. Zeotropic refrigerants such as R-407C with high temperature glide can fractionate 

in flooded evaporators during evaporation or condensing, creating significant performance 

issues (see Section 9.4.1.2.). 

9.2.1.2 Screw compressor chillers 

Air-cooled and water-cooled screw chillers below 700 kW commonly employ directexpansion (DX) evaporators. 

Chillers with capacities above 700 kW generally employ flooded evaporators. Flooded 

evaporators generally require higher charges than DX evaporators but permit higher 

efficiencies due to closer approach temperatures (the difference between the leaving water 

temperature and the saturated evaporator temperature). Air-cooled chillers employ fin-andtube condenser construction or microchannel condensers derived from automotive practice. 

Microchannel condensers are more compact for a given heat transfer capacity and allow the 

use of lower refrigerant charge in a chiller. 
140 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Screw compressors can be equipped with unloading devices such as slide valves or a port 

unloading mechanism that permit efficient operation at reduced volume flow rates. More 

recently, manufacturers are employing variable-speed drive devices with screw chillers. The 

application of variable speed lowers annualised energy consumption by eliminating the slide 

valves and associated losses, but can decrease full-load efficiency due to electronic drive 

losses. The benefits of screw compression (lack of surge limits present in centrifugal 

compressors) are combined with the benefits of variable-speed drives (efficient part loading 

and simpler screw compressor design) in properly designed systems to yield reduced seasonal 

energy consumption in water-cooled systems and air-cooled systems. 

Screw compressors can be fitted with intermediate pressure ports to accommodate an 

economiser in the chiller system. An economiser increases the energy efficiency and the 

cooling capacity of a chiller for a given compressor displacement. Economisers become more 

effective at higher lift conditions such as low temperature cooling or heat recovery (hot water 

supply) applications. 

9.2.1.3 Scroll compressor chillers 

Scroll compressors are available in capacities from 20 kW to 150 kW for a variety of 

refrigerants. Many scroll compressors are fixed speed machines with no unloading 

mechanism. However, they are frequently used in manifolded sets for a refrigerant circuit. 

This allows multiple scroll compressors to be used in chillers up to 1400 kW. Individual 

circuits and compressors can be turned off, making efficient capacity modulation possible. 

Scroll compressors with electromechanical mechanisms for unloading are available as are 

compressors with variable-speed electronic drives. 

Scroll compressor chillers are produced in both water-cooled and air-cooled versions. For 

capacities below 500 kW, brazed plate heat exchangers are commonly used for evaporators 

instead of the shell-and-tube heat exchangers employed in larger chillers. Brazed plate heat 

exchangers reduce system volume and refrigerant charge. They also are used as condensers 

for small water-cooled chillers. 

9.2.1.4 Reciprocating-piston compressor chillers 

Reciprocating compressors are similar in many ways to automobile engines and can be 

maintained and rebuilt in a similar manner. Reciprocating compressors have some advantages 

for units that operate over a variety of lift conditions because, unlike screw, scroll, and rotary 

vane compressors, they do not have a fixed volume ratio. Chillers with reciprocating 

compressors are produced in both water-cooled and air-cooled versions. Reciprocating chiller 

sales continue to decrease year by year although production still is significant, especially for 

lower capacities and for ammonia chillers. There is a relatively large inventory of older 

reciprocating chillers throughout the world. 

9.2.2. Absorption Chillers 

The energy source for absorption chillers is heat provided by a fuel-fired burner, steam, or hot 

water, though electricity still is required for internal solution pumps and controls. The steam 

or hot water generally is provided by a fuel-fired boiler or, less commonly, by heat recovered 

from industrial processes or cogeneration. In absorption chillers the compressor and motor of 

the mechanical vapour-compression cycle are replaced by two major heat exchangers (a 

generator and an absorber) and a solution pump. Absorption chillers also have condenser and 

evaporator heat exchangers. The refrigerant in large absorption systems commonly is water 

and the absorbent usually is lithium bromide, though lithium chloride also was common in the 

past and is still used though very infrequently. Absorption chillers may use an alternative 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 141

fluid pair: ammonia as the refrigerant and water as the absorbent, particularly in smaller 

capacities. 

Absorption chillers are identified by the number of heat input levels they employ (e.g., singleeffect or double-effect), and whether they are direct-fired with a burning fuel, or use steam or 

hot water as the heat source. 

Single-effect absorption applications, with lower efficiency, typically are limited to sites that 

can utilise waste heat in the form of recovered hot water or steam as the energy source or 

where boilers must be run year-round such as in hospitals. Other sites include co-generation 

systems where waste engine heat or steam is available. Hot fluid input temperatures typically 

range from 115o

 C to 135o C, although some machines can use temperatures as low as 90o C. 

Double-effect machines have an additional heat recovery heat exchanger and can be driven by 

hot water or steam or can be direct-fired. Typical steam input temperatures are 150o

 C to 205o

C (steam pressures from 650 to 1100 kPa). Double-effect absorption chillers can have 

primary-energy-based efficiencies that are 35 – 45% of those of vapour-compression systems. 

For example, double-effect absorption chillers can have a cooling coefficient of performance 

(COP) of 0.9 to 1.2 on a seasonal basis based on source energy input. Electrical vapourcompression systems can have a COP as high as 7.8, which must, in the case of thermal 

power plants, be multiplied by the heat-source-to-electricity delivery efficiency of the power 

plant and distribution system - around 35% for heat-driven generators that are predominant. 

Small double-effect gas-fired absorption chillers with capacities below 105 kW (30 RT) are 

used in Japan with water as refrigerant and lithium bromide as absorbent. 

Triple-effect machines have been developed and commercialised but are not used widely. The 

direct-fired high temperature generator in these machines operates at a temperature level of 

205o

 to 230o C which increases the cost and pressure level within the vessels. A fluid pair 

other than water/lithium bromide must be used in the high stage generator. 

9.2.3 Chiller Capacity Ranges 

Table 9-1 lists the cooling capacity range offered by single units of each type of chiller. (Most 

applications, particularly in larger capacities, use multiple chillers). 

Centrifugal chillers were the most common type of chillers above 700 kW capacity for many 

years. Reciprocating compressors were used in smaller chillers. Screw compressors have 

largely replaced reciprocating compressors in the range from 140 kW to 700 kW and are 

alternatives to centrifugal compressors up to about 1800 kW. Scroll compressors are 

alternatives to reciprocating compressors in the range from 10 to over 100 kW per 

compressor. Scroll compressors are used in chillers up to 1400 kW with 1 to 12 compressors 

per unit and multiple refrigerant circuits. Features such as novel unloading mechanisms and 

variable-high-speed electronic drives have been introduced on almost all compressor types, 

though not on all sizes. Lubricant-free operation and high–speed direct drive have been 

introduced with centrifugal compressors. 
142 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 9-1: Chiller Capacity Ranges

Chiller Type Approximate Capacity Range (kW) 

Scroll and reciprocating water-cooled 10 - 1,200 

Screw water-cooled 100 – 7,000 

Screw, scroll, and reciprocating air-cooled 10 – 1,800 

Centrifugal water-cooled 200 - 21,000 

Centrifugal air-cooled 200 – 7,000 

Absorption (generally ammonia-water) 15 - 90 

Absorption (generally water-lithium bromide) 20 – 18,000 

9.3 Developments and Trends in Chiller Markets 

9.3.1 Measures of Chiller Efficiency or Energy Use 

Energy efficiency, or the total power consumed annually, is the primary environmental 

consideration for chillers. While refrigerants each have an inherent Global Warming Potential 

(GWP) relative to CO2 (see Chapter 2, Refrigerants), refrigerants cannot contribute directly 

to global warming unless they are released to the atmosphere. Properly-maintained chillers of 

modern design emit very little of their refrigerant charge during operation. The dominant 

global warming effect caused by chiller operation is the CO2 and other greenhouse gases 

emitted in the combustion of fossil fuels generating the electricity to drive them. High 

annualised chiller efficiencies reduce global warming proportionally. /Cal93, San 97/

Key parameters used in describing the environmental effects of chiller operation are Total 

Equivalent Warming Impact (TEWI) or the similar and conceptually more complete Life 

Cycle Climate Performance (LCCP). These parameters are defined in Chapter 3 of /IPCC05/ 

and data for chillers are included in Chapter 5.2.4 of /IPCC05/. 

Other measures of chiller performance include the coefficient of performance (COP) which is 

the ratio of cooling capacity to the electrical input, both expressed in consistent units of 

energy or power. The COPs can be stated for any operating condition, but are commonly cited 

for full rated capacity. This condition establishes peak electrical demand which influences 

both overall power supply costs and the electricity demand costs paid by users as well as onsite transformer, switchgear, and related power supply costs. 

Each type of chiller and refrigerant combination has a best-in-class benchmark COP level that 

can be purchased. The benchmark COP level tends to increase as time passes and products are 

improved. The chillers with the best COPs tend to cost more because they employ larger heat 

exchangers and/or other special features. Many purchasers buy lower-cost, lower-COP 

chillers that meet or only slightly exceed minimum efficiency levels imposed by regulations, 

codes, or standards. With concern about increasing energy costs and growing interest in 

sustainability and “green buildings,” the trend is to select more efficient equipment. 

An additional measure of performance for individual chillers is called the Integrated Part 

Load Value (IPLV). This is described in ARI (now AHRI) Standard 550/590 /ARI03/. The 

IPLV metric is a weighted average of four COP values for an individual chiller, based on 

weighting by the percent of Ton-Hours assumed to be spent in each of four unequal size bins 

for load fraction, where the COP value for each bin is represented by one of four load 

fractions (25%, 50%, 75%, and 100%) each with different operating lift conditions. In Europe 

a similar part load parameter, ESEER, has been developed by Eurovent. This will be replaced 

in coming years by legal requirements coming from the Ecodesign directive for energy related 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 143

products where seasonal efficiency methods for cooling, heating, and refrigeration 

applications for chillers are currently established. The publication prEN14825 includes SEER 

and SCOP values for comfort cooling and heating applications. China implemented an IPLV 

standard in 2005 (GB 50189-2005). 

The IPLV concept provides a measure of performance over the seasons at part loads and/or 

reduced lift conditions. IPLV can be used as a basis for comparison of individual chillers and 

as a means for establishing a minimum energy efficiency parameter for code enforcement. 

The ARI Standard applies to an individual chiller serving a North American space 

conditioning load. It may not be the most accurate seasonal performance indicator for chillers 

serving other load profiles such as data centers, optimally-controlled systems using multiple 

chillers, or chillers operating in other climate conditions. 

9.3.2 Developments in the Market – Vapour-Compression Chillers 

Overlaps in the capacity range served by screw and centrifugal chillers, and scroll vs. screw 

chillers, are becoming larger. Reciprocating chillers are losing market share rapidly to scrolls 

and screws in small and large capacities respectively. Screw compressor development led to 

higher capacity and higher efficiencies in these machines. 

Larger scroll compressors and tandem scrolls are being used in multiples and in linked 

combinations of modular chillers to achieve capacities up to 1400 kW. These chillers 

increasingly are using R-410A refrigerant, displacing HCFC-22 use. 

The centrifugal chiller market has grown because of new construction and the need to replace 

chillers in developed markets, satisfy expanding infrastructure in emerging markets, and serve 

large process cooling and factory air conditioning applications. Higher capacity has been 

achieved by using dual compressors in a chiller and by use of multiple chillers. Counter-flow 

heat exchangers with dual compressors are used to improve efficiencies for large capacity 

chillers. Higher condensing temperatures in hot climates or for heat recovery/heat pump 

service are accommodated by multistaging compressors. 

In Southern Europe hydronic cooling systems (smaller capacity air-cooled chillers or air 

source heat pumps) are widely used. They are combined with fan coil units as low as 10 kW 

capacity for residential and light commercial buildings. 

In northern Europe, chillers of the scroll or screw types are widely used with air handling 

units and fan coil units in commercial buildings. 

While production of HCFCs is permitted in the developing countries beyond 2010, HCFC-22 

use in new equipment is decreasing, enabling these countries to benefit from the latest designs 

and technologies available. Developing countries that wish to export products to developed 

countries have a further incentive to accelerate their transition away from HCFC-22. 

China is now a large and growing market for chillers. The main market is East China with 

both a new construction and emerging replacement market. Screw and scroll chillers mostly 

still use HCFC-22, but new generations of scroll chillers are being designed to use R-410A 

and new screw chillers are employing HFC-134a. China has a major residential market for 

small chillers with fan coil units. 
144 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

9.3.3 Developments in the Market – Absorption Chillers 

Absorption chillers are manufactured and marketed primarily in Japan, China, India, South 

Korea and, additionally for capacities below 100 kW, Germany, Austria, and Italy. 

Absorption systems inherently are physically larger and have higher primary energy 

requirements and higher initial cost than vapour-compression chillers. They can be costeffective in applications where waste heat is available in the form of steam or hot water, 

where adequate or reliable electricity is not readily available for summer cooling loads, or 

where high electricity cost structures, including demand charges, make gas-fired absorption a 

lower-cost alternative. Absorption chillers can supply heating and cooling from one unit yearround without using fluorocarbon refrigerants and with a less expensive power supply system 

than mechanical chillers. 

High natural gas prices have slowed market development of direct-fired absorption systems in 

Japan, China, and Korea /JAR 08/. Concerns about the higher CO2 emissions from direct fired 

systems compared to the global warming impact of vapour compression chillers also is 

affecting the market. 

Trigeneration is the concept of deriving three different forms of energy from the primary 

energy source, namely, heating, cooling and power generation. Use of water-lithium bromide 

absorption chillers in trigeneration systems has been implemented in some countries. This 

concept also is referred to as CCHP (combined cooling, heating, and power generation). This 

option is particularly relevant in tropical countries where buildings need to be air-conditioned 

and many industries require process cooling and heating. Although cooling can be provided 

by conventional vapour-compression chillers driven by electricity, low quality heat (i.e. low 

temperature and low pressure) exhausted from the cogeneration plant can drive the absorption 

chillers so that the overall primary energy consumption is reduced. 

9.4 Current Refrigerant Choices and Options for Mechanical VapourCompression Chillers 

9.4.1 Positive Displacement Chillers 

9.4.1.1 HCFC-22 

Chillers that use positive displacement compressors (screw, scroll, and reciprocating 

compressors) employed HCFC-22 as the refrigerant of choice when they were first produced. 

Due to its low ozone depletion potential (ODP), HCFC-22 was viewed as a transition solution 

to phase-out of CFC-12 and other CFCs. Phase-down of HCFCs in developed countries 

started in 2004 leading to national regulations for HCFC-22 phase-out for new equipment by 

2010 or earlier. Europe phased out HCFC-22 beginning in 2000. Installed refrigerants, 

stocked inventories, and amounts recovered from retired equipment may be used to service 

existing equipment indefinitely if national rules permit. HCFC-22 still is offered for chillers in 

Article 5 countries. HCFC consumption must end by 2030 in developed countries and 2040 in 

developing countries.

9.4.1.2 HFC-134a, R-410A, and R-407C 

HFC-134a screw chillers were introduced early in the 2000s by a number of manufacturers in 

anticipation of the phase-out of HCFC-22 in 2010. Screw chillers using a higher pressure 

HFC refrigerant, R-410A, also have been introduced. For scroll compressor chillers, 

refrigerants being offered include HFC-134a, R-410A, and R-407C. R-410A now is the 

dominant refrigerant, especially for new scroll chillers. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 145

The zeotropic mixture R-407C served as a transition refrigerant, especially in European 

countries where HCFC-22 was phased out by regulations in advance of the Montreal Protocol 

deadlines. It allowed manufacturers to offer chillers with an HFC refrigerant (zero ODP) 

instead of HCFC-22 by making modest changes in their products. Unfavourable changes in 

heat transfer with R-407C necessitate larger, more expensive heat exchangers to maintain 

performance. R-407C has an appreciable temperature glide (5-7 K) so is not suitable for use 

in flooded evaporators that predominate in larger chillers. R-407C still is used in Europe and 

Japan as a replacement for HCFC-22 and elsewhere as one of a number of aftermarket service 

fluid options for retrofit. 

9.4.1.3 R-717 (Ammonia) 

Chillers employing R-717 as a refrigerant have been available for many years and are widely 

used in industrial systems (see Chapter 5, Industrial Refrigeration). There are a number of 

installations in Europe, the Middle East, China, and the U.S.A. R-717 chillers are available 

with open drive screw compressors in the capacity range 100-7000 kW. Chillers with open 

drive reciprocating compressors are available in the capacity range 20-1600 kW. 

R-717 chillers are manufactured in small quantities compared to HFC chillers of similar 

capacity. Different materials of construction are used because R-717 causes rapid corrosion of 

copper, the most widely used heat exchange surface in HCFC and HFC chillers. Plate-andframe steel heat exchangers are common in R-717 systems. Open drive compressors are used 

to avoid exposing copper motor windings to R-717. Semi-hermetic screw compressors have 

been developed with motors up to 110 kW using aluminium windings but are not common 

outside Japan. 

The current market for R-717 chillers is of the order of a thousand units annually compared to 

tens of thousands of chillers employing HCFC-22 and HFCs. R-717 is better suited to watercooled chillers because of higher costs of air-cooled R-717 condenser coils. Information on R717 chiller applications in building air conditioning is given in /Pea08a and Pea08b/. 

9.4.1.4 Hydrocarbons 

Chillers employing hydrocarbons as a refrigerant have been available for over 10 years, 

though typically only in small capacities (up to 200 kW) per refrigerant circuit. HC-290 

(propane) is used in chillers in air conditioning and industrial applications. HC-290 and 

another hydrocarbon, HC-1270 (propylene), are used in a limited number of small (<600 kW) 

air-cooled chiller installations in Denmark, Norway, the United Kingdom, Germany, and New 

Zealand. Some Article 5 countries such as Indonesia, Malaysia, and the Philippines are 

applying hydrocarbon chillers to large space cooling needs. The current market for 

hydrocarbon chillers is larger than for R-717 chillers on a global basis but still very small 

compared to the market for HCFC-22 and HFC chillers. 

Standards and guidelines for the use of hydrocarbon refrigerants in stationary refrigeration 

and air conditioning systems are provided in /ASH10a/ and /EN08/. EN 378 specifies 

maximum refrigerant charge sizes for systems located within occupied spaces of 1.5 kg and 

2.5 kg depending upon whether it is a public or private occupancy. For all refrigerant 

containing parts located outside, the upper charge size is 25 kg in public spaces. There is no 

limit if located in areas with authorised access only. International Standard IEC 60335-2-40 

permits up to approximately 5 kg of HC within a dwelling provided it is contained within a 

special enclosure /EN08/. Local authorities can impose different charge size limits or require 

special considerations. 
146 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

9.4.1.5 R-744 (Carbon dioxide) 

R-744 chillers have been introduced to the market by manufacturers in Europe. Both air- and 

water-cooled gas cooler versions are available. For rating purposes the chilled water range is 

+12/+7 o

C. The discharge temperature from the gas cooler is 30o C. Models with cooling 

capacities from 40 to 500 kW are offered. 

9.4.2 Centrifugal Chillers 

In the 1960s through early 1990s centrifugal chillers were offered with CFC-11, HCFC-22, 

CFC-113, CFC-12, CFC-114, and R-500 refrigerants. Of these, CFC-11 was by far the most 

common because it was the most efficient refrigerant for centrifugal chillers. With the 

implementation of the Montreal Protocol, production of chillers using CFCs or refrigerant 

blends containing CFCs (such as R-500) essentially ended in 1993 in developed countries and 

2005 globally. Centrifugal chillers using HCFC-22 were rarely produced after the late 1990s. 

The primary refrigerants used in centrifugal chillers today are HCFC-123 and HFC-134a. 

These alternative refrigerants began to be used in centrifugal chillers in late 1989 and 

continue to be used in new production chillers. HCFC-123 replaced CFC-11 and offers an 

efficient low ODP and very low GWP option. HFC-134a is a high GWP refrigerant but with 

only 13% of the ultra-high GWP of CFC-12 which it replaced. HFC-245fa, a foam blowing 

agent in the high GWP category, also can be used as a refrigerant in centrifugal chillers, but 

its use has been very limited. Table 9-2 shows the range of cooling capacities offered for 

centrifugal chillers with the refrigerants that replaced the CFCs. 

Table 9-2: Centrifugal Chiller Refrigerants 

Refrigerant Capacity Range (kW) 

HCFC-123 700 - 17,000 

HFC-134a 200 - 21,000 

HFC-245fa 2,600-8,800 

Centrifugal chillers also find application in naval submarines and surface vessels. These 

chillers originally employed CFC-114 as the refrigerant in units ranging in capacity from 440 

to 2800 kW. A number of CFC-114 chillers were converted to use HFC-236fa as a 

transitional refrigerant. (HFC-236fa has a very high GWP so has not been used in other chiller 

applications.) New naval chillers primarily use HFC-134a. 

9.5 Refrigerant Options for New Chiller Equipment 

The selection of alternative refrigerants to replace CFCs and HCFCs required a balance 

among thermophysical properties, chemical and thermal stability, global environmental issues 

of stratospheric ozone depletion and global warming due to refrigerant release and energyrelated effects, local safety issues such as toxicity and flammability, performance, and cost 

/Cal97/. 

Through better manufacturing techniques, all manufacturers are reducing leakage and 

minimising the direct effects of refrigerant releases on global warming. Average annual leak 

rates of 0.5% on a life cycle basis (including manufacturing, start-up, testing, operation, 

service, amortised catastrophic losses, and retirement) can be achieved by the best centrifugal 

chillers /Cal99/. Average annual leak rates of many chillers are higher, especially if they are 

not well maintained. Manufacturers are modifying chiller designs to reduce the refrigerant 

quantity that they require. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 147

9.5.1 Options for New Positive Displacement Chillers 

9.5.1.1 R-407C 

R-407C had a role as a transition refrigerant during the phase-out of HCFC-22. The 

development of new chiller products to use this HFC blend effectively has ended for reasons 

given in Section 9.4.1.2. 

9.5.1.2 Primary HCFC-22 replacements: HFC-134a and R-410A 

The transition away from HCFC-22 to HFC-134a in screw compressor chillers and to R-410A 

in scroll compressor chillers was under way by 2005 or earlier in developed countries. The 

transition is at an earlier stage in Article 5 countries. HCFC-22 refrigerant is less expensive 

than those alternatives, and development expenditures for new chillers and new compressors 

to use those alternative refrigerants can be postponed in these countries because they have 

later phase-out dates for HCFC-22. On the other hand, conversion to lower GWP refrigerants 

in higher efficiency systems would reduce climate change impacts.

9.5.1.3 HFC-32 

The refrigerant HFC-32 is used as a component in blends such as R-410A. It has been 

proposed for use as a refrigerant in positive displacement chillers by itself and in azeotropes 

with R-600 (n-butane), R-600a (isobutane), and other low GWP components because it has a 

moderate GWP, good energy efficiency, and high capacity in the vapour-compression cycle. 

Disadvantages include operating pressure levels higher than for HCFC-22 and flammability. 

HFC-32 is classed as an A2 refrigerant under ASHRAE Standard 34. /ASH10b/. A new rating 

for “low flammability” has been adopted (see Chapter 2, Refrigerants) and HFC-32 may be 

reclassified as A2L. Chillers using HFC-32 (other than as a blend component) have not been 

commercialised yet.

9.5.1.4 Additional HFC refrigerants: R-404A, R-507A, and other HFC blends 

High GWP refrigerants R-404A and R-507A have been considered as possible HCFC-22 

replacements in low temperature commercial refrigeration units. However, no non-flammable 

azeotrope has been commercialised for chillers for air conditioning that matches the pressuretemperature relationships of HCFC-22. 

Other HFC blends have been proposed by chemical manufacturers. Most of these blends have 

significant temperature glides (2 K or larger) and do not appear to offer performance benefits 

compared to HFC-134a or R-410A. Their market penetration in new equipment has been 

very small. Barriers to entry of new blends that do not offer significant performance or cost 

benefits include the challenges of developing long-term supply sources for chillers located 

around the world. 

Low GWP Refrigerants 

9.5.1.5 R-717 

If the use of R-717 refrigerant in chillers is to expand in the capacity range served by positive 

displacement compressors, particularly outside Europe, several impediments must be 

addressed: 

• Chiller costs typically are higher than for HCFC and HFC chillers. 

• Safety concerns with R-717 in comfort cooling applications can increase installation 

costs. Building codes in some countries heavily restrict applications but could be 

revised if acceptable safety is demonstrated with new approaches. 
148 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

The market for R-717 chillers is likely to grow in the future in regions where concerns about 

the control of high-GWP refrigerants are strong. However, perceived safety concerns in 

comfort cooling applications may increase installation costs and restrict installation 

arrangements. 

9.5.1.6 Hydrocarbons 

Use of HC-290 and HC-1270 for comfort cooling and heat pump applications is limited 

primarily by flammability concerns. 

There are hydrocarbon refrigerants with properties similar to those of HCFC-22 and HFC134a that allow use in new equipment of current design after appropriate adjustments for 

different material compatibility, lubricant, and safety aspects. Chillers employing 

hydrocarbon refrigerants are higher in cost than HFC chillers because they are manufactured 

in smaller quantities, though modification of equipment originally designed for HCFC-22 is 

fairly straightforward. 

Safety codes impose stricter requirements on hydrocarbon use for large refrigerant charges in 

chillers, particularly for indoor chiller installations (e.g., water-cooled chillers in machinery 

rooms). In regions where companies, government, and the public support hydrocarbon 

solutions, these safety concerns have been largely overcome by engineering, technician 

training, and changes in standards. In these regions, the use of hydrocarbon chillers is likely 

to grow in the future. However, in countries such as the U.S.A., regulations, building codes, 

and legal environments continue to pose difficulties for hydrocarbon use in commercial 

chillers. 

9.5.1.7 R-744 

R-744 air-cooled chillers have been introduced in the northern European market. In climates 

where the dominant cooling requirement is at an average ambient temperature of 150

 C or 

less, these systems can be equivalent in energy efficiency and LCCP with systems employing 

HFCs, R-717 or HCs. R-744 chillers will likely be less attractive at higher ambient 

temperatures due to decreasing efficiency with increasing ambient temperature. 

Where heat recovery to generate hot water at temperatures of 60o C or higher can be 

employed in a total energy strategy for a building, R-744 chillers offer the advantage of being 

able to use waste heat to raise water to higher temperatures with higher efficiency than other 

refrigerants. Chilled water can be used to sub-cool the refrigerant before expansion. For this 

application, R-744 heat recovery chillers provide good efficiency. 

9.5.1.8 HFC-1234yf and other unsaturated hydrofluorochemicals 

Chemical manufacturers are offering unsaturated hydrofluorochemicals (see Chapter 2, 

Refrigerants) to replace HFC-134a in mobile air conditioning (see Chapter 10, Vehicle Air 

Conditioning). If adopted widely in the mobile sector, further exploration of possibilities for 

use in stationary air conditioning (including chillers) and refrigeration is expected. Initial 

studies based on thermodynamic properties suggest that the COP of chillers using HFC1234yf refrigerant is not as good as for HFC-134a /Kon09 and Lec10/. Further development 

of unsaturated HFCs for chillers is under way /Kon10a, Kon10b, Kon10c and Spa08/ . It is 

not possible at this time to know whether HFC-1234yf and other such new refrigerants or 

blends will find significant acceptance for use in chillers. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 149

9.5.2 Options for New Centrifugal Chillers 

Centrifugal compressors are the most efficient technology in large units, namely those 

exceeding 1700 kW capacity. Water chillers employing these compressors are designed for 

specific refrigerants. 

9.5.2.1 Commonly used refrigerants: HCFC-123 and HFC-134a 

HCFC-123 and HFC-134a are the primary, well-proven current choices for new centrifugal 

compressor chillers. 

9.5.2.2 HFC-245fa 

HFC-245fa can be used as a centrifugal chiller refrigerant and at least one manufacturer 

markets chillers using this refrigerant /JAR08/. HFC-245fa is more commonly used for 

appliance insulation foam blowing. It went into commercial production in 2003. HFC-245fa 

has operating pressures higher than for HCFC-123 but lower than for HFC-134a. 

9.5.2.3 Design issues with zeotropes, hydrocarbons, and R-717 for centrifugal 

chillers 

Zeotropic refrigerants with significant temperature glides are not suitable for use in the 

flooded evaporators that are used in all centrifugal chillers. The discussion of refrigerant R407C in Section 9.4.1.2 explains the issues. 

Hydrocarbon refrigerants are in limited use in centrifugal chillers in petrochemical plants 

where a variety of very hazardous materials are routinely used and the staff is highly trained 

in safety measures and emergency response (see Chapter 5, Industrial Refrigeration). 

Hydrocarbon refrigerants have not been used in centrifugal chillers for air conditioning due to 

safety code restrictions and concerns with large charges of flammable refrigerants. 

R-717 is not a suitable refrigerant for centrifugal chillers because it requires a large number of 

compressor stages to produce the pressure rise (“lift” or “head”) required for the R-717 chiller 

cycle. Alternative designs using axial compressors are not commercialised for refrigeration 

systems. 

9.5.2.4 R-718 (water) 

The low pressures, high compression ratios, and high volumetric flow rates required in water 

vapour compression systems require compressor designs that are uncommon in the chiller 

field, though several companies and research projects have attempted their commercialisation. 

Applications for water as a refrigerant can chill water or produce an ice slurry by direct 

evaporation from a pool of water. R-718 systems carry a cost premium above conventional 

systems. The higher costs are inherent and are associated with the large physical size of water 

vapour chillers and the complexity of the compressor technology. Several developmental 

chillers and commercial vacuum ice makers have been demonstrated in Europe, Israel, and 

South Africa /Jah96, Oph08, and She01/. 

9.5.3 Issues with HCFC-123, HFC-134a, R-410A, and Other HFC Chiller Refrigerants 

Under terms of the Montreal Protocol, use of HCFC-123 in new equipment will end in most 

developed countries by 2020 and by 2030 in Article 5 countries. It already has stopped in 

Europe. Existing chillers may use installed, recovered, and stocked quantities of HCFC-123 

indefinitely (except in Europe). 
150 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Controls on the high GWP HFC refrigerants are beginning to be discussed by some countries 

and by international bodies. For stationary air conditioning applications such as chillers, the 

regulatory threshold defining high GWP has not been established yet. The GWPs of HFC134a, HFC-245fa, and R-410A make these refrigerants potential candidates for regulation (see 

Chapter 2, Refrigerants, for latest GWP values). Other HFC refrigerants discussed in this 

section 9.5 also have GWPs that make them potential candidates. 

There is no new refrigerant that has been commercialised yet to replace HCFC-123 or R410A. HFC-1234yf and other unsaturated hydrofluorochemicals, described in Section 9.5.1.8. 

above, are in early stages of evaluation for use in stationary air conditioning. It is not possible 

at this time to know whether these chemicals will find significant usage as a refrigerant in 

positive displacement chillers or as replacements in centrifugal chillers. 

A wide-ranging discussion of the progression of refrigerants from early uses to the present, 

addressing future directions and candidate refrigerants including “natural refrigerants”, is 

found in /Cal08/.

9.5.4 Alternatives to Vapour Compression Systems (Absorption Chillers) 

Absorption water chillers driven by hot water, steam, or direct firing are a viable alternative to 

the vapour-compression cycle for some installations. Absorption chillers have been described 

in Sections 9.2.2 and 9.3.3. 

9.6 Options for Existing Chiller Equipment 

When CFC and HCFC refrigerants are phased out (and in several countries that phased out 

HFCs), the functions performed by chillers employing those refrigerants have to be supported 

in one of the following ways: 

Retain/Contain: continued operation with stocked and/or reclaimed inventories in 

conjunction with containment procedures and equipment to reduce emissions. 

Retrofit: modification to allow operation with alternative refrigerants (HFCs) depending on 

applicable regulations. 

Replace: early retirement/replacement with new chillers (preferably having higher efficiency 

which reduces energy-related climate impact) using allowed refrigerants or not-in-kind 

alternatives, 

The retrofit options depend on the specific refrigerant for which the chiller was originally 

designed. When any retrofit is performed, it is recommended that the machinery room be 

upgraded to the requirements of the latest edition of safety standards /ASH10a, EN08/ or 

proposed international standards such as ISO/DIS 5149. It is also recommended that the 

manufacturers of the equipment be consulted in any retrofit program. 

The number of annual chiller retrofits is expected to decline significantly in developed 

countries where most economically-viable refrigerant conversions from CFC use have been 

completed. 

Today’s average centrifugal chillers use 20% less electricity than the average of chillers 

produced just two decades ago and the best chiller today uses less than 65% of the electricity 

of the average 1976 chiller /ICF03 and TEA04/. Building owners typically can pay back the 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 151

investment cost of replacing an old CFC chiller in three to five years (or less) in many regions 

that require cooling for more than three months a year. 

9.6.1 Positive Displacement Chillers 

A positive displacement compressor inherently can be applied to handle a number of different 

refrigerants and pressure ratios in a chiller so long as its motor has adequate power, the 

compressor, tubing, heat exchangers, and other components can meet pressure codes and 

regulations with the refrigerants, and the system materials and lubricant are compatible with 

the refrigerants. Despite this flexibility, there remain a number of issues in retrofitting 

positive displacement chillers to operate with new refrigerants. 

9.6.1.1 HFC-134a as a replacement for CFC-12 

The operating pressure levels and cooling capacities of HFC-134a and CFC-12 are similar. 

Thus, HFC-134a can be used as a retrofit refrigerant for CFC-12 chillers. The mineral oil 

lubricant used with CFC-12 must be carefully flushed from the system and replaced with a 

suitable synthetic oil that is compatible with HFC-134a (mineral oil is not miscible with 

HFCs, so cannot be used in HFC systems). If mineral oil and chlorides contained in the oil are 

not adequately flushed from the system, viscous deposits of contaminants may be formed in 

the system and clog small passages and controls. Other materials such as gaskets, elastomeric 

seals, and filter-driers must be checked for compatibility with HFC-134a and replaced if 

necessary. Control of moisture content in HFC-134a systems with synthetic oil requires more 

attention than with CFC-12. The chiller manufacturer should be consulted about the 

requirements for a successful retrofit. 

After conversion, the cooling capacity and energy efficiency of the system will be close to 

those of the system when charged with CFC-12. 

9.6.1.2 R-407C, HFC-134a, proprietary blends, and hydrocarbons as candidate 

replacements for HCFC-22 

Refrigerant HCFC-22 was employed in most new positive-displacement chillers until the 

latter half of the 1990’s. Based on a very extensive search of alternatives, it became clear that 

there is no direct substitution for HCFC-22 in chillers with flooded evaporators. 

Retrofit refrigerants for HCFC-22 initially used were R-407C and HFC-134a. A conversion of 

a chiller from HCFC-22 to HFC-134a will reduce cooling capacity by approximately onethird unless the compressor is replaced with one having about 50% greater displacement. In a 

conversion from HCFC-22 to either R-407C or HFC-134a, the mineral oil lubricant in the 

system must be removed and replaced with a synthetic lubricant compatible with HFCs. It is 

recommended that the manufacturer of the chiller be actively involved in any retrofit 

program. 

Alternative retrofit refrigerants for HCFC-22 equipment with DX evaporators include 

proprietary zeotropic and azeotropic blends of HFCs that have been and continue to be 

developed. The comments in Section 9.4.1.2 on R-407C explain problems with zeotropic 

blends which cause their use as an alternative in many HCFC-22 chillers to be accompanied 

by losses in capacity and energy efficiency. Some blends contain a small amount of 

hydrocarbon refrigerant so the blends may be used with mineral oil. Some blends are more 

suitable for air conditioning duty while others may be more appropriate for heat pump or 

refrigeration applications. When considering a blend for replacing HCFC-22 in a system, 

attention must be given to the effects of the blend upon cooling capacity and energy 

efficiency. 
152 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

New refrigerant blends coming into the market may have limited penetration because of 

concerns about long-term availability for service purposes and the reluctance of chiller 

manufacturers to warrant their equipment with refrigerants (and lubricants) they have not 

tested thoroughly. Such testing is an expensive process. 

Retrofit of hydrocarbon refrigerants into CFC or HCFC chillers is not permitted in many 

countries. However, in some jurisdictions (notably in South East Asia) numerous conversions 

have been completed. Cost may be incurred to incorporate safety features in the equipment 

and to modify the machinery room to meet safety standards. Conversion should only be 

planned and performed by suitably qualified engineers and technicians. 

9.6.1.3 R-404A or R-507A as replacements for HCFC-22 

Refrigerant blends R-404A and R-507A were developed for refrigeration applications as 

replacements for R-502, a blend that contains a CFC. The new blends have been successful as 

R-502 replacements for refrigeration duty. However, they are not attractive as replacements 

for HCFC-22 in chillers. Their energy efficiency for chiller operating conditions is lower than 

that of HCFC-22 and other alternatives discussed above. 

9.6.2 Centrifugal Chillers 

Centrifugal compressors by nature must be designed specifically for a particular refrigerant 

and a particular set of operating conditions for the refrigerant cycle in which they are used. 

Direct refrigerant substitution in centrifugal chillers can be made only in cases where the 

properties of the substitute refrigerant are nearly the same as those of the refrigerant for which 

the equipment was designed, or when the impeller speed and/or impeller geometry can be 

changed easily. In the past this has been accomplished by gear changes in open drive chillers 

and with variable speed drives in both open and hermetic compressor chillers. The 

compressor surge margin must be checked using the properties of the substitute refrigerant. 

In principle a refrigerant blend can be produced to accomplish substitution, but blends with 

significant temperature glide are unacceptable in the flooded evaporators of centrifugal 

chillers for reasons previously discussed. In practice, refrigerant substitutions are uncommon. 

R-423A has been used successfully as a replacement for CFC-12 in centrifugal chillers 

without the need for mechanical changes to the compressor in situations where the condensing 

temperature is not extreme. 

Complete replacement of a compressor by a design that is developed for an alternative 

refrigerant can be done, but this is uncommon because of the high cost of conversion. The 

primary alternative is to replace the chiller. 

9.6.3 Not-in-Kind Chiller Replacements – Absorption 

A factor which limits changeovers from CFC or HCFC vapour-compression chillers to 

absorption is the inability to retrofit in many existing buildings because the access ways are 

not large enough to allow for the absorption chiller to be delivered to the existing machine 

room. It is likely that the cooling tower capacity will need to be increased significantly. A 

suitable gas piping system should be prepared if a gas-fired absorption system is to be used. 

9.7 Banks and Emissions Relating to Chillers 

An annex entitled “Global inventories of the world-wide fleets of refrigerating and airconditioning equipment in order to determine refrigerant emissions: The 1990 to 2006 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 153

updating, Extracts from the FINAL REPORT” is provided with this RTOC report. The annex 

was prepared by Denis Clodic, Stephanie Barrault, and Sabine Saba of ARMINES in Paris, 

France, in April 2010. Section 8 of the annex presents information on chillers. Section 8 of 

the annex has not been reviewed or edited by the authors and contributors to this RTOC 

report’s Chapter 9. 

9.8 References 

 /ARI03/ Standard 550/590-03,"Water Chiller Packages Using the Vapor Compression Cycle", AirConditioning and Refrigeration Institute (ARI, now AHRI), Arlington VA, USA, 2003 

/ASH10a/ ANSI/ASHRAE Standard 15-2010, “Safety Standard for Refrigeration Systems”, American 

Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), Atlanta, GA, 

USA, 2010 

/ASH10b/ ANSI/ASHRAE Standard 34-2010, “Designation and Safety Classification of Refrigerants”, 

American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), 

Atlanta, GA, USA, 2010 

/Cal93/ Calm, J.M. “Global Warming Impacts of Chillers”, Heating/Piping/Air Conditioning 

Engineering, 65-2:28-39, February 1993 

/Cal97/ Calm, J.M., and Didion, D.A., “Trade-Offs in Refrigerant Selections: Past, Present and 

Future”, Refrigerants for the 21st Century, NIST, Gaithersburg, MD USA, American Society of 

Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), Atlanta. GA, USA, 6-19, 

October 1997; International Journal of Refrigeration, 21(4):308-321, June 1998 

/Cal99/ Calm, J.M., Wuebbles, D.J., and Jain, A.K., “Impacts on Global Ozone and Climate from Use 

and Emission of 2,2-Dichloro-1,1,1-trifluoroethane (HCFC-123)”, Journal of Climate Change, 

42(2): 439-474, June 1999 

/Cal08/ Calm, J.M., “The Next Generation of Refrigerants – Historical Review, Considerations, and 

Outlook”, International Journal of Refrigeration, 31(7): 1123-1133, 2008 

/EN08/ EN378: “Refrigerating Systems and Heat Pumps – Safety and Environmental Requirements” 

Parts 1-4, Comite Europeen de Normalisation, Brussels, 2008 

/ICF03/ ICF Consulting, “International Chiller Sector Energy Efficiency and CFC Phaseout”, report 

prepared for the World Bank, (Table 4), Washington D.C., USA, May 2003 

/IPCC05/ Intergovernmental Panel on Climate Change, Technology and Economic Assessment Panel, 

“Safeguarding the Ozone Layer and the Global Climate System – Issues Related to 

Hydrofluorocarbons and Perfluorocarbons”, Cambridge University Press, New York, NY, 

USA, 2005 

/Jah96/ Jahn, E., Lausen, D., and Paul, J., “Cooling of Mines with Vacuum Ice”, Proceedings of the 

FRIGA’96 Conference, Johannesburg, South Africa, 1996.03 

/JAR08/ Japan Air Conditioning, Heating & Refrigeration News (JARN), 25 November 2008, Serial 

No. 478-S 

/Lec10/ Leck, T.J., Kontomaris, K., and Rinne, F., “Development and Evaluation of High 

Performance, Low GWP Refrigerants for AC and Refrigeration”, Conference on Sustainable 

Refrigeration and Heat Pump Technology, Royal Institute of Technology (KTH), Stockholm, 

Sweden, June 13-16, 2010 

/Kon09/ Kontomaris, K. and Leck, T.J., “Low GWP Refrigerants for Centrifugal Chillers”, American 

Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), 2009 Annual 

Conference, Louisville, KY, USA, June 24, 2009 

/Kon10a/ Kontomaris, K. and Leck, T.J., “Low GWP Refrigerants for Air Conditioning of Large 

Buildings”, 10th REHVA World Congress, Sustainable Energy Use in Buildings, Antalya, 

Turkey, May 9-12, 2010 
154 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

/Kon10b/ Kontomaris, K., Leck, T.J., and Hughes, J., “A Non-Flammable, Reduced GWP, HFC-134a 

Replacement in Centrifugal Chillers: DR-11”, 13th International Refrigeration and AirConditioning Conference, Purdue University, Lafayette, IN, USA, July 12-15, 2010 

/Kon10c/ Kontomaris, K., “A Low GWP Replacement for HCFC-123 in Centrifugal Chillers: DR-2”, 

American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) and 

United Nations Environmental Programme (UNEP) Conference, Road to Climate Friendly 

Chillers – Moving Beyond CFCs and HCFCs, Cairo, Egypt, September 30-October 1, 2010 

/Oph08/ Ophir, A., “Mechanical Heat Pumps Using Water as Refrigerant for Ice Production and Air 

Conditioning”, presentation, International District Energy Association (IDEA), 99th Annual 

Convention in Orlando, FL, Westborough, MA, USA, 2008 

/Pea08a/ Pearson, A., “Ammonia’s Future”, ASHRAE Journal, American Society of Heating, 

Refrigerating, and Air Conditioning Engineers (ASHRAE), Atlanta, GA, USA, 50(2): 30-36, 

February 2008 

/Pea08b/ Pearson, A., “Water Chillers with Ammonia for Building Services”, Natural Refrigerants – 

Sustainable Ozone and Climate Friendly Alternatives to HCFCs, published by German 

Technical Cooperation Programme Proklima, German Federal Ministry for Economic 

Cooperation and Development, Bonn, Germany July 2008 

/San97/ Sand, J.R., Fisher, S.K., and Baxter, V.D., "Energy and Global Warming Impacts of HFC 

Refrigerants and Emerging Technologies", Alternative Fluorocarbons Environmental 

Acceptability Study (AFEAS) and U.S. Department of Energy (DOE), Washington, DC, USA, 

1997 

/She01/ Sheer, T.J., Butterworth, M.D., and Ramsden, R., “Ice as a Coolant for Deep Mines”, Chapter 

52, Proceedings of the 7th International Mine Ventilation Congress, Research and 

Development Center for Electrical Engineering and Automation in Mining, Krakow, Poland, 

June 2001 

/Spa08/ Spatz, M.W., “Latest Developments in Refrigerants for A/C&R Applications”, The 

International Symposium on New Refrigerants and Environmental Technology 2008, Kobe, 

Japan, November 20-21, 2008 

/TEA04/ UNEP Technology and Economic Assessment Panel, Chiller Task Force Report, United 

Nations Environmental Programme (UNEP), Ozone Secretariat, Nairobi, Kenya, May 2004 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 155

Chapter 10 

__________________________________________________________ 

Vehicle Air Conditioning 

Chapter Lead Author 

Jürgen Köhler 

Co-Authors 

William R. Hill 

Contributors 

Julius Banks 

Radim Čermák 

Michael Kauffeld 

Lambert Kuijpers 

Roberto de A. Peixoto 
156 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

10 Vehicle Air Conditioning 

10.1 Introduction 

Vehicles (cars, trucks, and buses) built before the mid-1990’s used CFC-12 as the refrigerant. 

Since then, in response to the Montreal Protocol, new vehicles with air conditioning have 

been equipped with systems using HFC-134a. (Abbreviation: A/C. In this report the 

abbreviation MAC for Mobile Air Conditioning is used). This chapter also covers the heat 

pump mode of the air conditioning cycle, for example systems used for heating BEVs– 

(battery-driven electric vehicles). By the year 2000, the transition from CFC-12 to HFC-134a 

as an OEM refrigerant, for factory installed AC systems, was complete in all developed 

countries. A US survey conducted by the Mobile Air-Conditioning Society Worldwide 

[MACSW] done for the IMAC project, indicates that even in 2005, approximately 19% of the 

US fleet still contain CFC-12 refrigerant. The survey includes vehicles that may have been 

equipped with CFC-12 when sold, but were later retrofitted to HFC-134a. Considering scrap 

rates and continued retrofitting, this percentage has likely dropped below 10% in 2010. 

Hence, it is expected that the demand for CFC-12 as a service refrigerant will be nearly 

eliminated in the next few years. Since the mid-1990’s, development of alternatives to HFC134a has been underway due to the high global warming potential [GWP] of HFC-134a. 

10.1.1 Regulatory Actions affecting Vehicle Air Conditioning and Refrigerants 

EU regulations, which control Mobile AC system direct emissions fall into two groups, 

controlling leaks and phasing out high GWP fluorinated GHG's. Directive 2006/40/EC 

covers both the emissions from air-conditioning systems in motor vehicles and the ban on use 

of refrigerants with a GWP greater than 150 in new type vehicles from January 1, 2011 and 

all new vehicles from 2017. EU Commission Regulation (EC) No 706/2007 includes a 

harmonised test for measuring leakages from mobile air conditioning systems. Commission 

Directive 2007/37/EC amends Annexes I and III to Council Directive 70/156/ clarifying some 

terms. Furthermore, this same regulation limits refrigerant emissions from mobile air 

conditioning, using refrigerants with GWP>150, to 40 g/y for single evaporator systems and 

60 g/y for dual evaporator systems beginning with new type vehicles in June 2008 and all 

vehicles in June 2009. 

European EU6 regulations were recently passed to limit the grams of GHG Green House Gas] 

(changed from CO2) emissions per kilometre initially to 130 gCO2/km and in 2012 down to 

95gCO2/km. Current directive 80/1268/EC is merged in EURO 5&6. This regulation also 

allows for a small credit for mobile air conditioning systems with efficient operation. In 

2011, the EU will publish a new Directive concerning measurement of MAC based CO2 

emissions. 

In Australia, a tax of about A$30/kg is proposed for HFC-134a from year 2011. 

In the USA, the state of Minnesota has passed a regulation requiring all manufacturers to 

report the leakage of the systems they sell in the USA as calculated as described in SAE 

standard J2727. The 2009 industry single evaporator MAC system data listed the average 

fleet emission loss at 14.1 g/y. This data is reported to consumers through a State of 

Minnesota website. Data is required to be updated with each model year. 

[http://www.pca.state.mn.us/climatechange/mobileair.html#leakdata] 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 157

Beginning 1 January 2009, all vehicles sold in California must carry a SMOG label indicating 

the level of Pollution attributed to each vehicle sold in California. This regulation [AB1229] 

also provides a level of credits for efficient and low leakage mobile air conditioning systems. 

The State of California also has a regulation [AB1493], which takes effect in the 2010 model 

year to restrict CO2 emissions of vehicles. This bill provides credits for AC direct and 

indirect equivalent CO2 emissions. Seventy percent of the allowable credit is related to 

indirect emissions and 30% is related in direct emissions. Early AC credits are available for 

model years 2009-2011. 

On October 30, 2009, the EPA published a final rule in the Federal Register 

(www.regulations.gov) under Docket ID No. EPA-HQ-OAR-2008-0508-2278 on the 

reporting of Greenhouse Gas emissions. This became effective December 29, 2009, with first 

reporting in March, 2010. As this relates to vehicle sources of HFC emissions, the reporting 

is delayed until 2011 and SAE J2727 is the proposed mechanism to report these emissions. 

[http://www.epa.gov/climatechange/emissions/ghgrulemaking.html] 

On September 15, 2009, the US EPA and the National Highway Transportation Safety 

Administration (NHTSA) proposed an historic National Program that would dramatically 

reduce greenhouse gas emissions and improve fuel economy for new cars and trucks sold in 

the United States. 

[http://epa.gov/otaq/climate/regulations.htm] 

The combined EPA and NHTSA standards will apply to passenger cars, light-duty trucks, and 

medium-duty passenger vehicles, covering model years 2012 through 2016. This rule requires 

fleet-wide net CO2 emissions reductions over the period 2012-2016. Regarding the impact on 

mobile air conditioning, a credit system for indirect CO2 emissions has been established. 

This credit system is based on a technology “menu” as shown in the table below. This rule 

provides credit for HFC-134a leakage reduction and use of low GWP refrigerant. Early A/Ccredits will be available for model years 2009 to 2011. 
158 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Table 10-1 Efficiency-Improving A/C Technologies and Credits 

Technology Description Estimated 

Reduction in 

A/C CO2

Emissions 

A/C 

Efficiency 

Credit 

(g/mi CO2) 

Reduced reheat, with externally-controlled, variabledisplacement compressor 30% 1.7 

Reduced reheat, with externally-controlled, fixeddisplacement or pneumatic variable-displacement compressor 20% 1.1 

Default to re-circulated air with closed-loop control of the air 

supply (sensor feedback to control interior air quality) 

whenever the ambient temperature is 75 °F or higher 

(although deviations from this temperature are allowed if 

accompanied by an engineering analysis) 

30% 1.7 

Default to re-circulated air with open-loop control air supply 

(no sensor feedback) whenever the ambient temperature 75 

°F or higher lower temperatures are allowed) 

20% 1.1 

Blower motor controls which limit wasted electrical energy 

(e.g., pulse width modulated power controller) 

15% 0.9 

Internal heat exchanger 20% 1.1 

Improved condensers and/or evaporators (with system 

analysis on the component(s) indicating a COP improvement 

greater than 10%, when compared to previous industry 

standard designs) 

20% 1.1 

Oil Separator (with engineering analysis demonstrating 

effectiveness relative to the baseline design) 

10% 0.6 

A new idle test cycle has been added starting in 2014 to qualify indirect MAC system credits. 

This idle test will quantify the amount of indirect CO2 emissions related to the MAC system. 

The indirect credit determined from the table above will be adjusted based on the results of 

the CO2 emissions related to MAC on the idle test on a sliding scale as described in the graph 

below. 

This graph and the table above were presented y the US EPA at the 2010 SAE 

Alternative Refrigerant and System Efficiency Symposium. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 159

There will also be a direct emissions credit as well based on the measurement of leakage as 

determined using the SAE standard J2727. This credit will represent about 50% of the total 

credit for MAC systems. 

In July, 2010, there was a workshop held as part of the SAE Alternative Refrigerant and 

System Efficiency Symposium. In this workshop, regulators, suppliers, and vehicle OEMs, 

discussed ideas of how MAC indirect emissions could be measured. The timing to 

introduction of the planned regulation in the USA is model year 2017. From the discussions 

in the workshop, it is considered likely that this continued co-operation will lead to a global 

unified approach regarding this matter. 

10.2 Technical Progress 

For sake of this report, mobile air conditioning systems are those used in passenger cars, light 

duty trucks, buses and rail vehicles. Passenger cars and light duty trucks have refrigerant 

charge amounts from 0.4-1.2 kg. Bus and rail vehicles can have refrigerant charge amounts 

from 2 kg to 15 kg and some even more. This report covers the new developments in this 

field since the 2005 IPCC TEAP report on Ozone and Climate and the RTOC 2006 report. 

For more details on the detailed system design and the history of refrigerant system 

development for these vehicles prior to 2005, see these reports. 

Driven by legislation (described in section 10.1.1) and competition with systems using 

alternative refrigerants (described in section 10.4) car air conditioning systems using HFC134a have become increasingly more leak tight and energy efficient. This has resulted in the 

introduction of new system concepts, including the use of internal heat exchangers, oil 

separators, and ejector cycles. New sealing concepts and improved hose materials are also 

being developed to reduce refrigerant direct emissions. Advanced research is being 

conducted on compressor expanders and there are increased applications of MAC to vehicle 

battery cooling. 

The rapid evolution of hybrid electric vehicles and electric vehicles with electrically driven 

compressors introduces new challenges for HFC-134a vehicle air conditioning systems. For 

these future mobility concepts a refrigerant has to be compatible with the electric motor of the 

compressor and with the oil used in these systems. Especially for battery driven electric 

vehicles, vehicle air conditioning systems for cooling as well as heat pump systems for 

heating have to be highly energy efficient because power consumed by MAC can 

significantly impact the vehicle driving range. Not only a HFC-134a system but any system 

using a new alternative refrigerant (described in section 10.4) faces these new challenges. 

10.3 Existing Mobile Air Conditioning Systems 

10.3.1 HFC-134a 

As already described in section 10.1.1 HFC-134a systems have become increasingly more 

leak tight. In some cases joint sealing technologies developed for R-744 have been adapted 

for use in HFC-134a systems. Hose materials and coupling designs for hoses have also been 

improved. In addition to that, HFC-134a systems show improved energy efficiency and fuel 

consumption (as mentioned section 10.2) to meet new regulatory requirements in the USA 

and driven by increased awareness of fuel consumption of MAC in the EU. For more details 

see also section 10.4.1.1. 
160 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

10.3.2 Retrofit of CFC-12 systems 

CFC-12 MAC systems continue to be retrofitted to HFC-134a as mentioned above. 

Furthermore, there are 14 other blend refrigerants that are approved by the USEPA under the 

SNAP regulation for retrofit of CFC-12 systems. Retrofit of HFC-134a and CFC-12 systems 

to hydrocarbons is still occurring in various regions, particularly in Australia and to some 

extent in North America even though vehicle OEMs and some regulatory bodies do not 

approve of this process due to inadequate safety mitigation. In the USA, the sale of CFC-12 

is restricted to certified technicians. However, HFC-134a is available to the general public. 

Retrofitting of CFC12 vehicles has declined after 1997 due to availability and price of CFC12. Retrofit cost in 1997 was $89.51and increased to $176.05 in 2003. Some vehicle MAC 

systems have also had control problems when retrofitted to HFC-134a causing a loss in 

system cooling performance 

10.4 Options for Future Mobile Air Conditioning Systems 

This report concentrates on vapour compression refrigeration cycle technology for vehicle air 

conditioning. The development status of other refrigeration technologies, like sorption or 

thermoelectric systems, are still far away from serial production and presently show very poor 

price competitiveness and poor system cooling performance and efficiency. 

10.4.1 Passenger Car and Light Truck Air Conditioning 

As seen in section 10.1, there is a large amount of regulatory activity related to passenger car 

MAC systems. The more recent focus is on the indirect impact of MAC vehicle emissions 

which is expressed for example in a paper by two European vehicle OEMs at the SAE 

ARSES meeting in July, 2010. An updated version of this was presented in European 

Commission workshop (Brussels, Oct 7th 2010). This may increase the importance of system 

efficiency as alternative low GWP refrigerant choices are made for MAC systems. This 

section covers the various refrigerants considered for use in passenger cars and light trucks 

that use refrigerant systems similar to passenger cars. All of the choices presented below have 

similar global warming impact, using the various methods of TEWI, LCCP, or LCA described 

in chapter 2 of this report. The comparison of the choices is often impacted more by the 

method and assumptions used than the actual performance. 

10.4.1.1 Improved HFC-134a Systems 

As the list of regulations grows limiting the use of HFC-134a, this may not be an option for 

mobile air conditioning systems in the future. HFC-134a systems with improved leakage 

rates and energy efficiencies might still be an intermediate option for some developing 

countries. 

In the year 2006 about 20 percent of the total global refrigerant emissions (CFC, HCFC, and 

HFC) are from passenger car MACs including the emissions in production, use, servicing, and 

end-of-life. Looking at HFC refrigerant emissions alone, emissions of MAC systems 

contributed to the total HFC refrigerant emissions with a 60 percent share in 2006 (see Annex 

Banks and Emissions). 

Significant research has been undertaken with regards to regular leakage rates of HFC-134a 

mobile air conditioning systems over the last five years. JAMA and ACEA conducted fleet 

tests, where the average leakage rate for these vehicles was 9.7-11.1 g/y. ACEA also 

sponsored laboratory investigations, which resulted in the development of the test procedure 

that is currently specified to meet the EU leakage regulation. Additional work was done by 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 161

the SAE IMAC CRP [Improved Mobile Air Conditioning Co-operative Research Program] in 

the USA. The average leakage in the four systems evaluated by IMAC was 12.9 g/y. This 

project went further to evaluate alternative improved technologies and demonstrated that a 

50% improvement in leakage rate is feasible based on three single evaporator systems and one 

dual system tested. The average result is similar to the ACEA/JAMA studies. Further work 

was done for the California Air Resource Board (CARB) analysing five different systems 

typical of those in high volume use in California and these laboratory results indicate 

predicted average field leakage of 8.9 g/y. From all this work one could draw the conclusion 

that much of the atmosphere loading that has been reported for HFC-134a is not due to 

regular leakage, but due to emissions from irregular leakage, improper service, inadequate end 

of life recovery and the service of CFC-12 systems with HFC-134a; much of this is 

controllable by improved service and enforcement of vehicle end-of-life reclamation 

procedures. A recent paper by Stella Papasavva, et al. does a good job of examining some 

low and high leak scenarios, summarising many of the other leakage studies. This analysis 

compares well when examining the sales of HFC-134a that has occurred in recent years. The 

table below summarises the analysis of leakage from different sources from this paper: 

Leakage Type Low Leak Scenario [g/y] High Leak Scenario [g/y] 

Regular Leakage Rates 13.6 15.0 

Irregular Leaks 17.0 17.0 

Service Leaks 4.4 7.8 

End-of-Life leaks 11.1 50.0 

Total 46.1 89.8 

These results might also be modified based on the local rules for recovery and recycling. One 

difference to other older studies is that the assumption of average system charge is lower with 

this analysis [550 grams]. This has been the trend over the last ten years as vehicle OEMs 

have strived to reduce system size and charge to reduce mass and cost. 

With the introduction of the credit system in the USA, and also upcoming legislation in 

Europe more vehicle OEMs are introducing technologies to reduce energy consumption with 

HFC-134a refrigerants. The SAE IMAC co-operative research group demonstrated that 30% 

reduction in energy consumption of the MAC system is possible. Many of these technologies 

are now being used in current production HFC-134a systems, for example, internal heat 

exchangers, oil separators in compressors, increased use of externally controlled compressors, 

etc. 

10.4.1.2 Carbon Dioxide (R-744) Systems 

R-744 refrigerant charge amounts are typically reduced by 20-30% as compared to HFC-134a 

systems. The SAE CRP1234 performed a risk assessment of R-744 systems as compared to 

HFC-1234yf and determined that the risks are low and similar. R-744 demonstrated slightly 

higher risks than HFC-1234yf. SAE standards have been developed to cover service best 

practices, safety practices, and refrigerant purity of R-744. At present, the US EPA is 

considering the application of R-744 as a refrigerant for MAC with use restrictions under the 

US Clean Air Act’s Significant New Alternatives Policy (SNAP) Program. The EPA 

indicated that the final ruling should be issued early in 2011. 

R-744, with appropriate system design and control changes, has been shown to be comparable 

to HFC-134a with respect to cooling performance and total equivalent CO2 emissions due to 

MAC systems, and qualifies for use in the EU under the current impending regulation 

(Directive 2006/40/EC). 
162 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Currently, technical hurdles (reliability, leakage, NVH especially system noise) and 

commercial challenges (additional costs) exist that will require resolution prior to the 

implementation of R-744 as a refrigerant for car air conditioning. 

At present, no OEMs or suppliers are working on R-744 as an alternative refrigerant solution. 

R-744 heat pumps are presented as possible heating systems for hybrid and battery driven 

electric vehicles. In comparison to electric resistance heaters (PTC heaters) which reduce 

significantly the vehicle driving range, heat pumps operate at a higher level of efficiency and 

offer the advantage of reducing only moderately the vehicle driving range. 

10.4.1.3 HFC-152a Systems 

Because of its flammability, HFC-152a would require additional safety systems. Refrigerant 

charge amounts in a direct expansion system could be reduced by 25-30% as compared to 

HFC-134a and with a secondary loop system, typically 50%. Industry experts have discussed 

using R-152a, but only in a secondary loop type system. The added costs, system weight 

increases and size constraints present obstacles to implementation. The US EPA has studied 

the potential use of HFC-152a as a refrigerant under the US Clean Air Act’s Significant New 

Alternatives Policy (SNAP) Program and has SNAP-listed HFC-152a as refrigerant with the 

following use condition: 

• Engineering strategies and/or devices shall be incorporated into the system such that 

foreseeable leaks into the passenger compartment do not result in HFC-152a concentrations of 

3.7% v/v or above in any part of the free space inside the passenger compartment for more 

than 15 seconds when the car ignition is on. 

HFC-152a in a secondary loop system has been shown to be comparable to HFC-134a with 

respect to cooling performance and equivalent CO2 emissions due to MAC systems and 

qualifies for use in the EU under the aforementioned regulations. 

At present, no car manufacturer has selected HFC-152a as the refrigerant for MAC serial 

production due to technical or commercial issues related to the secondary loop system. Most 

development activity has been focused on using this refrigerant in a secondary loop system 

(SLS) as a means of assuring safe use. A secondary loop system utilises glycol and water as 

the direct coolant in the passenger compartment with this coolant being cooled under-hood by 

the refrigerant. Prototype vehicles have been demonstrated by several of the OEMs. At the 

2010 SAE 2010 ARSES meeting, an USA OEM indicated they still have some development 

on-going with this alternative. An Italian OEM presented an EU financed project with R134a SLS (not R-152a) not yet finalised development for mass production. With many new 

vehicle designs, using a secondary loop system may have advantages for idle stop, cooling 

batteries or on board electronics cooling. It also reduces the amount of refrigerant required 

for multi-evaporator installations since chilled coolant is circulated throughout the vehicle not 

refrigerant. 

10.4.1.4 Blend Alternatives 

In early 2006, several chemical companies announced new non-flammable refrigerant blends 

to replace HFC-134a in Europe. One was an azeotropic blend of CF3I and HFC-1234yf 

(2,3,3,3-tetrafluoroprop-1-ene). Two other formulations were zeotropic blends of HFC1234yf, HFC-1225ze, HFC-1225ye, HFC-32, and minor concentrations of HFC-134a. These 

refrigerants were never classified by ASHRAE or proposed to the USEPA for SNAP 

approval. All the blend alternatives had a GWP less than 150 meeting EU requirements for 

low GWP refrigerants. 

In 2006, the ACEA, VDA, SAE, and Japanese Automobile Manufacturers Associations 

assisted in co-operative efforts to evaluate these refrigerants. The refrigerant blends were 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 163

withdrawn by chemical companies in the fourth quarter 2007 after discovering chronic 

toxicological effects and some stability effects. 

Other low GWP blend alternatives are still under consideration for mobile air conditioning as 

well as for other stationary applications. 

10.4.1.5 Hydrocarbons and Blends containing Hydrocarbons 

In Australia and the USA, hydrocarbon blends have been introduced as drop-in refrigerants to 

replace CFC-12 and to a lesser extent for HFC-134a. The real number of cars that have been 

retro-fitted with such HC refrigerant blends is unknown but it seems to be a significant 

number. The retrofits with HCs are legal in some Australian states and illegal in others and in 

the USA. US EPA has forbidden the uses of HCs for retrofit but has considered the possible 

use of HCs for new systems, providing safety issues are mitigated. 

HCs or HC-blends, when correctly chosen, present suitable thermodynamic properties for the 

vapour compression cycle and permit high energy efficiency to be achieved with well 

designed systems. Some studies have been carried out using hydrocarbons in indirect systems 

(same system as the secondary loop system presented above for HFC-152a). Nevertheless, 

even with indirect systems, HCs are so far not seen by vehicle manufacturers as replacement 

fluids for mass-produced AC systems due to safety concerns. 

10.4.1.6 HFC-1234yf Systems 

The unsaturated HFC-1234yf, qualifies for use in the EU under the aforementioned 

regulations. Due to increased density of HFC-1234yf versus HFC-134a, it may be possible to 

reduce charge amounts. HFC-1234yf performance could also benefit from use of an internal 

heat exchanger. In this case, HFC-1234yf charge amounts could be expected to increase 5-

15%. Manufacturers are working now on ways to reduce the system volume to reduce 

refrigerant charge further due to the cost of HFC-1234yf as compared to HFC-134a. HFC1234yf is a new chemical which recently received EPA Pre-manufacture Notice (PMN) and is 

currently undergoing EPA SNAP review. The EPA is expected in the near future to issue 

their final rule on this substance and potentially associated use restrictions. It has been 

registered for high volume applications by REACH review/regulation in the EU. The high 

volume REACH application was submitted in February 2009. As with HFC-152a, use of any 

flammable substitute is subject to US state safety conditions on flammable refrigerants. The 

US EPA has reported that barriers to EPA SNAP listed refrigerants have been removed in all 

states. 

The German Federal Institute for Materials Research and Testing (BAM) has investigated the 

flammability of HFC-1234yf. They found that in the case of HFC-1234yf leakages the 

probability to produce explosive atmospheres in the presence of hydrocarbons (less than 1%, 

which can occur in the engine compartment due to gasoline or cracked oil) is larger than that 

of HFC-134a leakages, but this explosive atmosphere is less than that which exists with pure 

hydrocarbons. They also found that the formation of hazardous amounts of HF when HFC1234yf is exposed to ignition sources (like open flames and hot surfaces with temperatures of, 

for example, 350°C or 500°C) is critical. Their tests were carried out in comparison to HFC134a which can also form HF when exposed to ignition sources. The BAM report states that 

HFC-134a is not as reactive as HFC-1234yf so that the hazards regarding HF formation is 

judged to be lower for HFC-134a than for HFC-1234yf. Vehicle manufacturers have 

explained that these tests were not done in a way that is typical of the under-hood 

environment as most of the tests were done in a sealed chamber. Only a few of these tests 

were actually done in a real car. 
164 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

HFC-1234yf in a direct evaporation system has been shown to be comparable to HFC-134a 

with respect to cooling performance and equivalent CO2 emissions due to MAC systems with 

some system modifications, and qualifies for use in the EU under the aforementioned 

regulation. 

In a global Cooperative Research Program administrated by SAE the refrigerant was tested in 

numerous laboratories concerning material compatibility, thermo-chemical stability, toxicity 

of refrigerant, and decomposition products, and flammability of the refrigerant. The results 

showed no compatibility and stability issues. A detailed Fault Tree Analysis (FTA) focussing 

on potential risk due to refrigerant flammability, toxicity and decomposition products has 

been completed. Based on the results it is concluded that HFC-1234yf is acceptable for use in 

mobile air conditioning from a toxicity perspective. Risk assessments have concluded there is 

an extremely low probability of ignition of refrigerant associated with HFC-1234yf during an 

accidental release. With the application of new safety standards, the specific requirements of 

HFC-1234yf are considered to maintain the safety of the vehicle at today’s level. 

In November 2009, all major global car OEMs have concluded after extensive testing and 

analysis that HFC-1234yf can be used as a global replacement refrigerant in future mobile air 

conditioning systems and it can be safely accommodated through established industry 

standards and practices for vehicle design, engineering, manufacturing, and service. 

Currently, still hurdles (miscibility with oil, stability problems in the presence of small 

amounts of water and air in the air conditioning system, mixing with HFC-134a, additional 

costs) exist that will require resolution prior to the commercial implementation of HFC1234yf as a refrigerant for passenger car air conditioning. 

HFC-1234yf requires a different chemical process route in comparison to that of HFC-134a 

and a simple conversion of existing assets is not possible. Two North American chemical 

companies have announced the installation of a new HFC-1234yf production plant in order to 

supply market demand after regulatory approval. These companies now share patents on the 

use of this refrigerant in MAC systems and other manufacturers will have to purchase a 

license to manufacture. 

One US American OEM has announced its intention to use HFC-1234yf in serial production 

vehicles from 2013. Other vehicle OEMs have expressed their interest in HFC-1234yf but 

have not yet officially announced a commitment to use HFC-1234yf as refrigerant for A/C 

serial production. OEM’s indicate that they will design HFC-1234yf MAC systems in that 

way that these systems can safely be used with the refrigerant HFC-134a as well. This will 

affect the world-wide transition from HFC-134a to HFC-1234yf for MAC systems. The 

emerging choice for global car manufacturers’ seems to be HFC-1234yf at this time. Based 

on the previous industry transition from CFC-12 to HFC-134a, it can be seen that HFC-134a 

will be used as a service refrigerant for 10-15 years after regions convert to HFC-1234yf. 

10.4.2 Bus and Rail Air Conditioning 

World-wide, approximate 50% of the bus and train fleet is still equipped with HCFC-22 

systems. The rest use mostly HFC-134a or R-407C systems. Most new bus or train air 

conditioning systems are equipped with the refrigerants HFC-134a or R-407C. The only 

reported low GWP refrigerant activities are on-going fleet tests of R-744 systems in buses. 

Currently, reliable leakage data on mobile air conditioning systems for short and long distance 

buses and railway vehicles is only reported for Europe, based on a study conducted on behalf 

of the European Commission. The study is based on 2,000 report forms on inspections of 

systems installed in short and long distance buses in Sweden. It empirically established the 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 165

annual leakage rate for the use phase of the vehicles. In buses recharges or topping-off (gasand-go) are carried out in relatively short service intervals to compensate for leakages 

whatever their nature. Such refills are recorded over a sufficiently long time and in 

appropriate detail in Sweden where annual inspection is mandatory for every installation with 

a refrigerant charge of HFCs of more than 3 kg. 

Based on a statistical analysis of the recorded refill data, the study concludes that the average 

leakage rate of new MACs (2000 and newer) in diesel driven long distance buses is 1.20 ± 

0.74 kg/y and is of the same magnitude as leak rates from MACs of new short distance buses 

with diesel drive, with 0.92 ± 0.40 kg/y. Taking into account that typical refrigerant charges 

of bus air conditioning systems are about 10 kg that means that the annual leakage rates of 

new buses are about 10 % of the original charge. However, as the buses age the leakage rates 

increase. Buses built before 2000 had leakage rates at least twice as high. 

In comparison to short and long distance buses leakage rates of air-conditioning systems of 

rail vehicles are much lower, with 5% of the original refrigerant charge per year for the vast 

majority of the vehicles. Typical charge amounts of rail air-conditioning systems are higher 

than 10 kg per system. Depending on its length, a train might be equipped with several of 

these systems. 

At present, no regulation exists worldwide on fluorinated greenhouse gases used as 

refrigerants for MAC systems in buses and trains. It is likely that the choice of refrigerant of 

passenger car air conditioning systems will influence the choice of refrigerant for air 

conditioning systems in buses and trains. 

10.5 References 

1234yf OEM group: Update 1234 as a replacement for R134a, MAC Summit, Scottsdale, 2008. 

Andersen, Stephen O., Kristen N. Taddonio, US EPA Climate Protection Partnerships Division, New 

Realities In MAC Refrigerant Choice, Stephen, MACs Convention, 06 February 2009. 

[http://www.epa.gov/cppd/mac/2010-mac-annualmtg-0120.htm] 

Arkema Press Release, Arkema launches an industrial production project in Europe of a low-GWP* 

fluorinated gas for automotive air-conditioning, July, 2008. 

ARMINES Reference 70890, Arnaud Tremoulet, Youssef Riachi, David Sousa, Lionel Palandre, Denis 

Clodic, Evaluation of the Potential Impact of Emissions of HFC-134a from Nonprofessional 

Servicing of Motor Vehicle Air Conditioning Systems, CARB Agreement No. 06-341, July, 

2008. 

ASHRAE Position Document on Natural Refrigerants, American Society of Heating, Refrigerating and 

Air-Conditioning Engineers, Atlanta, 28 January, 2009 

(http://www.ashrae.org/aboutus/page/335). 

Automobiltechnische Zeitschrift, September 14, 2009: 

http://www.atzonline.de/Aktuell/Nachrichten/1/10454/ixetic-CO2-Waermepumpe-optimiertThermomanagement-von-Elektroautos.html 

Automobiltechnische Zeitschrift, September 1, 2010: 

http://www.atzonline.de/index.php;do=show/alloc=1/lng=de/id=12319/site=a4e 

Baker, James, Mahmoud Ghodbane, John Rugh, William Hill, Alternative Refrigerant Demonstration 

Vehicles, SAE ARSS 2007 

Baker, James A., Revising J-2727, 2006 ARSS. 

Bang, Scott, Comparative Life Cycle Assessment on Alternative Refrigerants, SAE ARSS 2008 

Bang, Scott, Evaluation Result of HFO-1234yf as an Alternative Refrigerant for Automotive Air 

Conditioning, VDA Winter Meeting, 2008 
166 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Clodic, D., G. El Khoury, Energy consumption and environmental footprint of MAC system of full 

hybrid vehicles, VDA Winter Meeting, 2009 

Bauer, I., Transport Refrigeration – Current Technologies, Market and Trends, Master Thesis 

Karlsruhe University of Applied Sciences, May 2006 

Comments to the HFC-1234yf SNAP proposal: Risk Assessment for Alternative Refrigerants HFO1234yf and R-744 (CO2) Phase III report, Dec. 18, 2009 

Bouvy, Claude, Kälte aus Wärme - Adsorptionstechnik für die Klimatisierung im Automobil, ATZ - 

Automobiltechnische Zeitschrift, 04/2010 

Caretto, L. and Monforte, R., Safety Issues in the Application of a Flammable Refrigerant Gas in MAC 

Systems: The OEM Perspective [Revised July, 2009]”, SAE 2009-01-0541, SAE 2009 World 

Congr. Proc., Detroit (MI), USA, Apr 20÷23rd, 2009 

Comments to EPAs proposed ruling: 

[http://www.regulations.gov/search/Regs/home.html#documentDetail?R=0900006480a6df2d], 

Dr. Thomas Lewandowski, Gradient Corporation 

Additional Comments on the EPA SNAP proposal can be found at the following link at 

www.regulations.gov: 

http://www.regulations.gov/search/Regs/home.html#searchResults?No=70&Ne=11+8+8053+8

098+8074+8066+8084+1&Ntt=EPA-HQ-OAR-2008-

0664&Ntk=All&Ntx=mode+matchall&N=0 

Cox, N. , V. Mazur, D. Colbourne, New High Pressure Low- GWP Azeotroic And Near-Azeotropic 

Refrigerant Blends, 12th International Refrigeration and Air Conditioning Conference, Purdue 

University, July, 2008. 

Directive 2006/40/EC of the European Parliament and of the Council of 17 May 2006 relating to 

emissions from air-conditioning systems in motor vehicles and amending Council Directive 

70/156/EEC, Official Journal of the European Union L161/12 (2006). 

DuPont and Honeywell: Guidelines for Use and Handling of HFC-1234yf. 2008. 

DuPont, Honeywell: Announcement of the installation of a new HFC-1234yf production plant, 

http://www51.honeywell.com/honeywell/news-events/press-releasesdetails/10_0520_Honeywell_Dupont.html, May, 2010 

Elbel, Stefan, Pega Hrnjak, Experimental Validation of a CO2 Prototype Ejector with Integrated HighSide Pressure Control, VDA Winter Meeting, 2007 

Eustice, Harry, Assessment of Alternate Refrigerants for EU Regulations, SAE Phoenix, ARSS, June 

2008 

GM announcement: 

http://media.gm.com/content/media/us/en/news/news_detail.brand_gm.html/content/Pages/news

/us/en/2010/July/0723_refrigerant 

Graaf, Marc, The Influence of the Accumulator and Internal Heat Exchanger Design as separate and 

combined Components on the System Behaviour of a R744 A/C System, VDA Winter Meeting, 

2005 

Graz, Martin, Investigation on Additional Fuel Consumption for a R134a and R744 AC – System in a 

VW Touran, VDA Winter Meeting, 2009 

Grimm, Ulrich, Complex Interactions of Low GWP Refrigerants, A/C Oils, and Materials in MAC 

Circuits, Automotive Refrigerant and System Efficiency Symposium, SAE, Scottsdale, July 13-

15, 2010. 

Hammer, Hans, Results of Audi A5 Evaluation with Alternate Refrigerants, SAE ARSS 2008 

Heckt, Roman, Cost efficient R744 AC System for Compact Vehicles, VDA Winter Meeting, 2005 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 167

Hekkenberg, M., Anton J.M. Schoot Uiterkamp, University of Groningen, Center for Energy and 

Environmental Studies IVEM, Nijenborgh 4, 9747 AG Groningen, The Netherlands, Exploring 

policy strategies for mitigating HFC emissions from refrigeration and air conditioning, 

international journal of greenhouse gas control 1 (2007) 2 9 8 – 3 0 8 

Holtappels, K., BAM Test Report II-2318/2009, Determination of the explosion region of ethaneHFO1234yf-air mixtures, BAM Federal Institute for Materials Research and Testing, 12200 

Berlin, November 17, 2009, 

http://www.umweltbundesamt.de/produkte/dokumente/test_report_hfo1234yf.pdf [also available 

on EPA SNAP website] 

Holtappels, K., BAM Test Report II-2318/2009 I, Ignition behaviour of HFC-1234yf, BAM Federal 

Institute for Materials Research and Testing, 12200 Berlin, June 22, 2010, 

http://www.umweltbundesamt.de/produkte/dokumente/test_report_hfo1234yf_2010_06.pdf 

Honeywell Patents: EP1716216B1, US patents 7279451 and 7534366, available at 

http://www.freepatentsonline.com/ 

Hrnjak, Pega, Technological and theoretical opportunities for further improvement of efficiency and 

performance of the refrigerant candidates achievements and potentials of efficiency increase, 

VDA Winter Meeting, 2007 

Ikegami, Tohru, Masahiro Iguchi, Kenta Aoki, Kenji Iijima, New Refrigerants Evaluation Results, 

VDA Winter Meeting, 2008 

Ikegami, Tohru, Masahiro Iguchi, Kenta Aoki, Kenji Iijima, New Refrigerants Evaluation Results, 

SAE ARSS 2008 

IPCC/TEAP Special Report on Safeguarding the Ozone Layer and the Global Climate System: Issues 

Related to Hydrofluorcarbons and Perfluorcarbons, 2005 Prepared by Working Group I and III 

of the Intergovernmental Panel on Climate Change, and the Technology and Economic 

Assessment Panel, Cambridge University Press, Cambridge, United Kingdom and New York, 

NY, USA, 488 pp. 

Jung, Dongsoo, Yoonsik Ham, Performance of R429A and R430A to replace HFC134a in mobile airconditioners, Phoenix 2007, ARSS. 

Koehler, J., Strupp, N. C., Kling, M. E., and Lemke, N. C.: Refrigerant comparison for different 

climatic regions. The International Symposium on New Refrigerants and Environmental 

Technology, Kobe, 20-21 November 2008. 

König, Holger, Rüdiger Roth, Part 1: Development of a supercritical CO2-test rig Part 2: CO2-State of 

the Art in Industrial Refrigeration, VDA Winter Meeting, 2005 

Kozakiewicz, Agnieszka, and Steininger, Nikolaus, The Regulatory Approach to MACs in the 

European Union, ARSES , July, 2010 

Low, R. E.: Update on INEOS Fluor Refrigerant Development Program. VDA Winter Meeting, 

Saalfelden, 11-12 February 2009. 

Low, R.E.: Minderung des Einflusses von Klimaanlagen auf die Umwelt – Perspektiven von INEOS 

Fluor, DKV Annual German Refrigeration and Air Conditioning Conference, Berlin, November 

18-20, 2009 

Magnetto, Daniela, Carloandrea Malvicino, Thermal Systems Integration for Fuel Economy, SAE 

Phoenix ARSES, July, 2010 

Malvicino, C., The 4 Fiat Pandas Experiment and other considerations on refrigerants, SAE ARSS 

2008 

Malvicino, Carloandrea, B-Cool, Low Cost and High Efficiency CO2 Mobile Air Conditioning system 

for lower segment cars, VDA Winter Meeting, 2005 

Man-Hoe Kim, J.-S. Shin, W.-G. Park, S. Y. Lee, The Test Results of Refrigerant R152a in an 

Automotive Air-Conditioning System, Phoenix ARSS 2008. 

Meininghaus, Roman, Dietmar Fischer, MAC Energy Efficiency, 1. A Broader Perspective, 2. Aspects 

of Virtual Testing, VDA Winter Meeting, 2009 
168 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Meyer, John, R1234yf System Enhancements and Comparison to R134a, SAE ARSS 2008 

Monforte, R., B. Rose, J-M. L’Huillier, Fiat, Renault and PSA outlook on the selection of a Global 

Alternative Refrigerant, SAE ARSS 2007 

Monforte, R., B. Rose, J-M. L’Huillier, Updated situation about alternative refrigerant evaluation, SAE 

ARSS 2008 

Monforte R., MAC System Fuel Consumption in various climate conditions, SAE ARSS 2007 

Monforte, Roberto, Carloandrea Malvicino, Tim Craig, Secondary Loop System for small cars, 2nd 

European Workshop on MACS & Auxiliaries, Mirafiori Motor Village, Torino - 29/11/07. 

Monforte, Roberto, Alternative Refrigerants, Assessment of the Environmental Impact of MACS and 

Investigation of its reduction drivers, VDA Winter Meeting, 2008 

Morgenstern, Stefan, R744 MAC Status and System Standardization, VDA Winter Meeting, 2008 

Nelson, Brain, Air Conditioning Credits in the Light-Duty GHG Rule (and Beyond), SAE ARSES, 

July, 2010 

Papasavva, Stella, William R. Hill, Assessing the Life Cycle Greenhouse Gas Emissions of HFC-134a, 

HFC-1234yf and R-744 using GREEN-MAC-LCCP©, VDA Winter Meeting, 2009 

Papasavva, Stella, William R. Hill, GREEN-MAC-LCCP© Global Refrigerants Energy & 

Environmental – Mobile Air Conditioning - Life Cycle Climate Performance, SAE ARSS 2007 

Papasavva, Stella, Deborah J. Luecken, Robert Waterland, Kristen Taddonio, Stephen Andersen, 

Estimated 2017 Refrigerant Emissions of 2,3,3,3-tetrafluoropropene [HFC-1234yf] in the 

United States Resulting from Automobile Air Conditioning, Environmental Science 

Technology, Nov., 2009 

Peral-Antunez, Enrique and Rose, Bruno, MAC fuel consumption “simple-test” methodology, 

Comparison of test benches, engine types and MAC technologies, ARSES, July, 2010 

Updated at European Commission workshop (Brussels, Oct 7th 2010) 

(the document is available on CIRCA website 

http://circa.europa.eu/Members/irc/enterprise/wltp/library?l=/meetings/100907_mac&vm=detail

ed&sb=Title ) 

Petitjean, Christophe, Jugurtha Benouali, R-1234yf Validation and A/C System Energy Efficiency 

Improvements, Automotive Refrigerant and System Efficiency Symposium, SAE, Scottsdale, 

July 13-15, 2010. 

Porrett, Ken, Eric Scarlett, 1234yf System Evaluation, SAE ARSS 2008 

Restuccia, Giovanni, Angelo Freni, Salvatore Vasta, Alessio Sapienza, Fabio Costa, An innovative 

prototype of adsorption chiller for mobile air conditioning, Thermal and Environmental Issues 

in Energy Systems, ASME Conference, Sorrento, Italy, May 2010 

Riegel, Harald, Efficiency of Mobile Air Conditioning, SAE ARSS 2008 

Riegel, Harald, Efficiency of Refrigerant Circuits – Comparison of Alternative Refrigerants, SAE 

ARSS 2007 

Riegel, Harald, Status of R744 Development, VDA Winter Meeting, 2007 

Rinne, Frank, HFO-1234yf Technology Update-Part I, VDA Winter Meeting, 2009 

Rose, Bruno, E. Peral-Antunez, MAC fuel consumption “simple-test” methodology, Comparison of 

test benches, engine types and MAC technologies, Phoenix SAE ARSES, July, 2010 

SAE, http://www.sae.org/mags/sve/6323, 14 May 2009 (information regarding composition AC-4 

blend, containing HFC-1243-zf) 

SAE, http://www.sae.org/standardsdev/tsb/cooperative/crp1234-3.pdf, 10 November 2009 (information 

regarding CRP1234 Report) 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 169

Schwarz, W. and Rhiemeier, J. M.: The analysis of the emissions of fluorinated greenhouse gases from 

refrigeration and air conditioning equipment used in the transport sector other than road 

transport and options for reducing these emissions, Maritime, Rail, and Aircraft Sector. Final 

Report prepared for the European Commission (DG Environment), 

(07010401/2006/445124/MAR/C4) 2 November 2007. 

Schwarz, W.: Establishment of Leakage Rates of Mobile Air Conditioners in Heavy Duty Vehicle, Part 

2 Buses and Coaches. Final Report prepared for the European Commission (DG Environment), 

(ENV.C.1/SER/2005/0091r) 31 January 2007. 

Sciance, Fred : Improved Mobile Air Conditioning Cooperative Research Program, Presented at the 

SAE 2006 Automotive Alternate Refrigerants Systems Symposium, Scottsdale, AZ, June 2006, 

SAE International, Warrendale, PA 15096-0001. 

Spatz, Mark, Barbara Minor, HFO-1234yf Low GWP Refrigerant: A Global Sustainable Solution for 

Mobile Air Conditioning, SAE ARSS 2008 

Spatz, Mark, HFO-1234yf Technology Update-Part 2, VDA Winter Meeting, 2009 

Spatz, Mark, Barbara Minor, HFO-1234yf A Low GWP Refrigerant For MAC, Honeywell / DuPont 

Joint Collaboration, VDA Winter Meeting, 2008 

Strupp, Niels Christian, Betriebsverhalten von Verflüssigern in automobilen Kältekreisläufen, Ph.D. 

thesis, University of Braunschweig, Braunschweig, January 2011 

Thundiyil, K.: Refrigerant choice under SNAP. VDA Winter Meeting, Saalfelden, 11-12 February 

2009. 

U.S. Environmental Protection Agency (2004), Risk Analysis for Alternative Refrigerant in Motor 

Vehicle Air Conditioning. U.S. EPA, Washington D.C. 

U.S. Environmental Protection Agency (2009),, Report of the EPA Working Group on R744 (Working 

Document), Kristen Taddonio, Lead Author, U.S. EPA, Washington D.C. 

UNEP (United Nations Environment Program): UNEP Refrigeration, Air Conditioning an Heat Pumps 

Technical Options Committee (RTOC), 2006 Report of the Refrigeration, Air Conditioning and 

Heat Pumps Technical Committee, 2006 RTOC Assessment Report, United Nations 

Environment Program, Nairobi, January 2007, 235 pp. 

VDA announcement, Frankfurt am Main, 20 October 2008, 

http://www.vda.de/en/meldungen/news/20081020.html. 

VDA announcement, Frankfurt am Main, 6 September 2007, 

http://www.vda.de/en/meldungen/archiv/2007/09/06/1690/. 

Wazlak, Klaus, Die klimafreundliche Kühlung: Berliner Verkehrsbetriebe fahren mit 

umweltschonenden CO2-Klimaanlagen. Press release of the Berliner Verkehrsbetriebe BVG, 

Holzmarktstraße 15-17, 10179 Berlin, July 2, 2010. 

Wertenbach, Juergen, Overview of Alternate Refrigerants, SAE Phoenix, ARSS 2007 

Weinbrenner, Marcus, Link, Joachim, Strauß, Thomas, Kroner, Peter, Senkung des 

Kraftstoffverbrauches im Winterbetrieb. In: Haus der Technik: PKW-Klimatisierung VI. 

Expert-Verlag, November 2009, pp.47–63 

Whang, D., D. Crane, J. LaGrandeur, Design and Analysis of a Thermoelectric HVAC System for 

Passenger Vehicles, SAE 2010 World Congress & Exhibition, April 2010, Detroit, 2010 

Wieschollek, Florian, Dr. Roman Heckt, Improved Efficiency for Small Cars with R-744, VDA Winter 

Meeting, 2007 

Wiesmueller, Joachim J., Status of R744 Deployment and Way Forward, VDA Winter Meeting, 2006 

Wolf, Frank, R744 the Global Solution Advantages & Possibilities, VDA Winter Meeting, 2007 

www.pca.state.mn.us/climatechange/mobileair.html#leakdata. 

Yang, J., F.R. Stabler, Automotive Applications of Thermoelectric Materials, Journal of Electronic 

Materials, Vol.38, No.7, p.1245-1251, 2

2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 171

Chapter 11 

__________________________________________________________ 

Refrigerant Conservation 

Chapter Lead Author 

Julius Banks 

Lead Authors or Co-Authors 

Radim Čermák 

Horace Nelson 

Sulkhan Suladze 

Paulo Vodianitskaia
172 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

11 Refrigerant Conservation 

11.1 Introduction 

Refrigerant conservation may be viewed as both an effort to extend the life span of refrigeration and 

air-conditioning equipment by establishing efforts to recover, recycle, and reuse refrigerants. 

Refrigerant conservation also involves practices to ensure access to and proper disposal of so called 

“refrigerant banks” held in existing equipment. Refrigeration system leak elimination is fundamental 

to refrigeration conservation and should be emphasised through appropriate practices." 

Recovery means the removal and temporary storage of refrigerant that has been removed from a 

system undergoing service or disposal. Recycling means the passing of recovered refrigerant through 

filters in order to make the refrigerant suitable for reuse. Such practice is generally not intended for 

used refrigerant that will be repackaged and placed back into commerce. Reclamation involves 

processes that remove impurities (such as non-condensables, moisture, or acid), in essence, 

reprocessing used refrigerant back to virgin specifications based on industry purity standards (e.g., 

AHRI Standard 700-2004 and SAE J1991). Whereas, destruction involves Protocol accepted 

technologies (typically thermal incineration) that effectively destroy ODS to established destruction 

removal efficiencies. 

Conservation efforts should be placed on refrigerant recovery at the point of installation and continue 

throughout service and ultimate equipment end-of-life. Conservation is achieved by incorporating 

efforts of governments, equipment and chemical manufacturers, as well as equipment 

owners/operators to develop life cycle approaches aimed at reducing refrigerant emissions. 

Conservation efforts have also included taxation of banked refrigerants, required training of service 

personnel, limited access to ozone-depleting refrigerants, mandated service practices that reduce 

emissions by maintaining leak tight systems, recovery of refrigerant during equipment service and 

equipment end-of-life, established market for the resale and reuse of used refrigerants, and providing 

for the destruction of stockpiled or banked refrigerants. 

The continuing phase-out (or as the case for many Parties to the Protocol a phase-down) on the 

consumption and production of ozone-depleting HCFC refrigerants has resulted in the use of zero 

ODP and in many instances low GWP refrigerants as a service fluid for existing systems via a retrofit 

or conversion from an ODS to a non-ODS refrigerant. 

Recovery/recycling/reclaiming requirements have been implemented for a few years in different 

countries and have demonstrated proven results. These requirements have been established in 

conjunction with phase-out requirements of ODS refrigerants. However, many countries have yet to 

implement such requirements. Few countries have developed comprehensive conservation policies 

including recovery, leak tightness, and destruction of stockpiles. 

Refrigerant emissions to the atmosphere are often called losses without identification of the cause. 

The specific identification of refrigerant emissions is necessary to limit fugitive emissions. 

Refrigerant emissions consist of the following: 

• Fugitive emissions whose source cannot be precisely located 

• Tightness degradation due to temperature variations, pressure cycling, and vibrations that can 

lead to unexpected and significant increases of leak flow rates 

• Component failures from poor construction or faulty assembly 

• Losses due to excessive equipment vibration 

• Losses due to refrigerant handling during maintenance (e.g., charging the system), and 

servicing (e.g., opening the system without previously recovering the refrigerant) 

• Accidental losses (e.g., natural disasters, fires, explosions, sabotage, and theft), 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 173

• Losses at equipment disposal that is due to venting, rather than recovering refrigerant at the 

end of the system’s life 

11.2 Recovery, Recycling, and Reclamation 

The need to conserve or recovery refrigerant has led the industry to develop a specific terminology 

which is used in this section /ISO/: 

- Recover means to remove refrigerant in any condition from a system and store it in an external 

container. 

- Recycle means to extract refrigerant from an appliance and clean it using oil separation and single or 

multiple passes through filter-driers which reduce moisture, acidity, and particulate matter. Recycling 

normally takes place at the field job site. 

- Reclaim means to reprocess used refrigerant, typically by distillation, to specifications similar to 

that of virgin product specifications. Reclamation removes contaminants such as water, chloride, 

acidity, high boiling residue, particulates/solids, non-condensables, and impurities including other 

refrigerants with different boiling points. Chemical analysis of the refrigerant shall be required to 

determine that appropriate specifications are met. The identification of contaminants and required 

chemical analysis shall be specified by reference to national or international standards for new 

product specifications. Reclamation typically occurs at a reprocessing or manufacturing facility. 

 - Destruction means to destroy used refrigerant in an environmentally responsible manner. 

11.3 Refrigerant Recovery and Recycling Equipment 

The purpose of refrigerant recovery and recovery/recycling equipment is to help prevent emissions of 

refrigerant by providing a means of temporarily storing refrigerants that have been removed from 

systems undergoing service or disposal. Such equipment is used to temporarily store recovered 

refrigerant until the system undergoing repair is ready to be recharged or is prepared for disposal. 

Refrigerant recovery equipment may have the ability to store (recovery only) or the added capability 

of recycling (recovery and recycling) refrigerants. The temporary storage capability of the equipment 

prevents the release of refrigerants into the atmosphere that may otherwise exist if the refrigeration 

and air-conditioning equipment were opened to the atmosphere for service. 

The use of refrigerant recovery and recycling equipment is the most essential means of conserving 

refrigerant during the service, maintenance, repair, or disposal of refrigeration and air-conditioning 

equipment. Refrigerant recovery and recycling equipment should be made available to service 

technicians in every sector. Please note that due to incompatibility issues and the array of refrigerants 

used in different sectors that refrigerant recovery/recycling equipment intended for use with one type 

of air-conditioning system, such as motor vehicle air conditioners, may not be adequate to service airconditioning and refrigeration equipment in the domestic, unitary, or commercial refrigeration and 

air-conditioning sectors. The types of refrigerants used in these sectors vary and all 

recovery/recycling equipment is not capable of meeting the same requirements. This important note 

should be made known to users to make certain that their recovery equipment is capable of handling 

the specific refrigerants that are used in the system. The specific identification of the equipment is 

important throughout its service, disposal or end-of-life. 

Recycling equipment is expected to remove oil, acid, particulate, moisture, and non-condensable (air) 

contaminants from used refrigerants. These recycling performances can be measured on contaminated 

refrigerant samples according to standardised test methods /ARI 700/. Unlike reclaiming, recycling 

does not involve analysis of each batch of used refrigerant and, therefore, it does not quantify 

contaminants nor identify mixed refrigerants /Kau92/. Consequent restrictions have been placed on 

the use of recycled refrigerant, because its quality is not proven by analysis. 

A variety of recycling equipment is available over a wide price range. Currently, the automotive airconditioning industry is the only application that prefers the practice of recycling and reuse without 
174 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

reclamation. Acceptance in other sectors depends on national regulation, recommendation of the 

cooling system manufacturers, existence of another solution such as a reclaim station, variety and type 

of systems, and the preference of the service contractor. Reuse of recovered without strict adherence 

to refrigerant type-specific service fittings may result in unintended releases of mixed refrigerants. 

Mixed refrigerants are often costly to separate which may provide incentive for intentional release of 

cross contaminated refrigerants. Recycling with limited analysis capability may be the preference of 

certain developing countries where access to qualified laboratories is limited and shipping costs are 

prohibitive. For most refrigerants there is a lack of inexpensive field instruments available to measure 

the contaminant levels of reclaimed refrigerant after processing. At the same time the use of 

reclamation equipment which provides maximum separation of oil, acid, hard particle contaminants, 

moisture and air is to be preferred in countries where verification of processed refrigerant by proper 

chemical analysis is available. 

Refrigerant recovery equipment has been developed and is available with a wide range of features and 

prices. Some equipment with protected potential sources of ignition also exist for recovery of 

flammable refrigerant. Testing standards have been developed to measure equipment performance for 

automotive /SAE/ and non-automotive /ISO/ applications. Although liquid recovery is the most 

efficient, vapour recovery methods may be used alone to remove the entire refrigerant charge as long 

as the time is not excessive. Excessive recovery times should be avoided, since extended recovery 

time periods may increase the service call time of technicians. Extended service call times may limit 

the number of service calls that technicians can perform, which in turn may limit the practical usage 

of recovery equipment. In order to reach the vacuum levels that are required in some countries for 

larger systems, vapour recovery will be used after liquid recovery /Clo94/. Performance standards for 

refrigerant recovery equipment are available for service of both motor vehicle air conditioners (e.g., 

SAE J1990), and stationary refrigeration and air-conditioning systems (e.g., ARI Standard 740-1998 

and as are AHRI Standards for certifying. Adoption of such standards as a part of common service 

procedures should be adopted by regulating authorities. 

11.4 Technician Training and Service Certification 

An increasing number of governments have realised the need for technician certification programs 

and /or certified companies to ensure proper handling of regulated products. Training requirements 

may differ depending on the type of equipment being serviced. Training programs should be 

structured on the type of equipment that the technician intends to service. For example, the level of 

training for the service of residential refrigerators should differ from that for centrifugal chillers. 

HFCs blends have seen increased usage in multiple end-uses sectors. It is imperative that technicians 

are properly trained in the proper use and handling of all refrigerant alternatives. 

Hydrocarbons have wide acceptability in many small appliances. As a means of making certain that 

only trained personnel have access to refrigerant, many countries have implemented sales restrictions 

on refrigerants to certified technicians. 

In the U.S., a technician certification program has been established. This program is for individual 

technicians, as well as companies, that perform maintenance, service, repair, or disposal of 

refrigerants reasonably expected to release those refrigerants into the atmosphere. The program 

requires different levels of certification depending on the type of equipment that the technician 

intends to service or dispose: motor vehicles; small household appliances; or low-pressure, highpressure, and very high-pressure appliances. The U.S. emphasises this technician certification by 

limiting the sales of ODS refrigerants to certified technicians. 

In many countries strict training and certification requirements for refrigeration technicians who 

handle refrigerant gases are already a legal requirement. {Insert text on the EU F-Gas Regulations 

(EC 842/2006) and the associated Regulation for training and certification of individuals and 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 175

companies (EC 303/2008). The F-Gas Regulations were introduced from 4 July 2007. Member states 

were required to establish training and certification requirements for individuals by 4 July 2008 and 

companies were required to be certified by 4 July 2009. In addition the EU ODS Regulations (EC 

2037/2000) were re-cast as Regulation EC 1005/2009 with effect from 1 Jan 2010. 

. 

In Japan, obligations of recovery operators are specified by the Fluorocarbons Recovery and 

Destruction law. As one of the obligations, recovery operators must be authorised as “registered 

recovery operators.” Recovery operators must also have technicians certified by a government 

recognised authority. The technician training and certification program was started in 1994 by the 

concerned associations of installers, equipment manufacturers and refrigerant manufacturers. Since 

the program’s inception, the training seminars have been held for the staff of recovery operators 

throughout the country. The total number of technicians who have passed the final examination and 

received the certificate during the past 12 years reached nearly 50,000. 

In Poland, a total 1,840 persons were trained, out of which nearly 94% passed the final examination 

and received the “Green Card”. This certificate ascertains the serviceman’s ability to repair and 

execute the maintenance of refrigeration and air-conditioning equipment in accordance with all the 

ecological requirements. Those who successfully pass the training and certification procedure acquire 

important information (the new types of ecological refrigerants, the main international agreements 

aiming at protecting the ozone layer) /BU01/. 

One key element of RMP and RMP-update programs accomplished in countries of Eastern Europe, 

Caucasus and Central Asia was to initiate training in Good Practices to reduce the CFC demand 

through introduction of proper methods for leak reduction and recovery. As an example, Republic of 

Georgia improved training capacities of vocational schools that educate technicians in refrigeration or 

air conditioning field through upgrading of vocational schools curriculum and equipment and 

competency of teachers. 

Belize reported to the UNEP in 2004 that their CFC consumption is below the level required in the 

approved action plan. Since its implementation, the National Ozone Unit has successfully 

implemented a Refrigerant Management Plan, enacted a comprehensive legal framework to address 

ozone depleting substances, conducted a public awareness programme, and reduced national CFC 

consumption by half, from 24.89 ODP tonnes in year 1998 to approximately 12 ODP tonnes in 2005. 

The country’s success can be partially attributed to its establishment of a certification and licensing 

scheme for refrigerant technicians.

11.5 Refrigerant Reclamation, Separation, Destruction 

11.5.1 Reclamation and Separation 

One means of conservation is the establishment of a reclamation scheme. Reclamation involves the 

recovery and reclamation of used refrigerant back to virgin specifications. Once reclaimed, used 

refrigerants are repacked and sold to new users. Reclamation is essentially, a market-based industry. 

If there is no demand for a particular refrigerant, the costs to send recovered refrigerant to reclamation 

facilities will be a disincentive to reclaim. Efforts must be initiated early on with refrigerant supply 

companies to support the take back of used refrigerant. Many service establishments (particularly for 

motor vehicle air-conditioning) will not be able to afford storage for recovered refrigerants awaiting 

reclamation. The cost of sending small quantities of recovered refrigerant to reclamation facilities is a 

disincentive to reclamation efforts. Such disincentives promote venting of stockpiled refrigerant. 

Care should be taken by policy makers to eliminate parallel (and potentially illegal) routes to market. 

Such avoidance of improperly reclaimed used refrigerants requires strict auditing of the refrigerant 

distribution chain. 
176 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Reclamation practices, which process used refrigerant back to near virgin specifications, are necessary 

to protect the quality of the refrigerant stock as well as the equipment containing the refrigerant. 

Likewise, reclamation also extends the lifespan of the refrigerant and decreases the dependency on 

virgin refrigerant by placing it back into service and prolonging the use of used refrigerants. 

Countries that have implemented mandatory reclamation requirements have found incremental 

increases in the amount of refrigerant reclaimed. France, where reclaimed refrigerant totals have been 

gathered, shows an evolution in the efficiency of the recovery program /SAU96/. In 1992, without 

any regulation, 200 metric tonnes of recovered refrigerant (CFCs & HCFCs) were reclaimed. In 

1993, after making recovery mandatory and carrying out a deposit-refund scheme, the quantity grew 

to 300 tonnes and the number of refrigeration companies concerned doubled from 200 to 400 out of 

2500. In this example government incentives were necessary to reach full development of recovery 

schemes. It also shows that making recovery a habit requires some time. 

An extensive survey conducted in Australia /BEN01/ traced the paths of imported refrigerants through 

the sales and application chain. The survey assessed the amount and type of product that may be 

placed back into service, and concluded that service contractors are recovering approximately 400 MT 

of product (CFCs and HCFCs) annually from systems during servicing. 

Reclaimed refrigerant refers to refrigerant which has been processed and verified by analysis to meet 

specifications that are similar to newly manufactured product specifications, such as those provided in 

ARI 700 /ARI700/. There is technically very little difference between virgin and reclaimed 

refrigerant. One exception is the allowable content of specific hazardous or toxic components that 

result from the manufacture or decomposition of virgin fluorocarbons. 

The use of reclaimed refrigerant has the advantage of avoiding possible system breakdowns, as a 

direct result of contaminated refrigerant, which might lead to refrigerant emissions. As reclaimed 

refrigerant meets new product specifications, it often has the support of equipment manufacturers who 

maintain guarantees on their equipment. One advantage to reclaiming is that the measurements of 

refrigerant, which have actually been recovered, are easily obtained. However, reclamation does 

require a costly infrastructure, which may only prove viable when potential for financial return of 

recovered refrigerant is sufficient to overcome the initial investment of the company performing 

reclamation. 

Mixed refrigerants, meaning refrigerants that are cross contaminated during the recovery process, are 

of concern due to their negative impact on systems’ performances, possible equipment damage if 

reused in another system, and the high cost for their disposal. This condition of mixture can be 

caused by chemical reactions such as in a hermetic compressor motor burnout, but more likely by bad 

service practices. The following steps can be taken to minimise the probability of mixing refrigerants: 

1. Properly clean recovery units, including all hoses and cylinders in accordance with 

manufacturer’s suggestions or dedicate a piece of recovery equipment to equipment suspected 

to contain mixed refrigerant; 

2. Test and identify suspect refrigerant (for example, by using a refrigerant identifier) before 

consolidating into larger batches and before attempting to recycle or reuse the refrigerant; 

3. Keep appropriate records of refrigerant inventory; 

4. Label refrigeration and equipment systems with the identity of their refrigerants, especially 

upon retrofit of older systems to new refrigerant; and 

5. Mark cylinders used for recovered and/or recycled refrigerants. 

It is very difficult to determine the presence of mixed refrigerants without a laboratory test. If the 

nature of the refrigerant is in doubt, the saturation pressure and temperature may be checked and 

compared with published values. However, this method may be rendered unreliable by inaccurate 

pressure gauges or contamination by non-condensables. A thorough review of the service history, if 

existing and an understanding of the current problem may provide additional insight. Field 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 177

instruments capable of identifying R-12, R-22 and R-134a refrigerants at purity levels of 97% or 

better are now available. 

In automotive applications where R-12 and R-134a dominate the market, standards have required 

separate recycling equipment. In addition they have adopted unique vehicle service ports, service 

hoses, and service equipment fittings to prevent inadvertent mixing. Hoses have separate connectors 

for R-12 and R-134a cooling systems and must be properly labelled /SAE/. 

The development and wide distribution of replacement refrigerant blends has increased the risks of 

mixtures, and the complexity of separating them. Currently, the high cost of refrigerant blends has 

limited the profitability of separation. 

The U.S. has mandated that refrigerant reclaimers return refrigerant to the specifications (including 

the purity level) specified in ARI Standard 700 and verify the specifications using the laboratory 

protocol set forth in the same standard. In addition, reclaimers must release no more than 1.5% of the 

refrigerant during the reclamation process and must dispose of wastes properly. This mandate limits 

the number of persons allowed to reclaim refrigerant, and reinforces the U.S. mandate that used 

refrigerant be reclaimed prior to resale to a new owner. 

Japan reported that 690 tonnes/year of CFCs are recycled or reclaimed for reuse in refrigeration and 

air-conditioning equipment. This represents 56% of the total estimated recovered quantity of 1230 

tonnes/year. 

The United States government has mandated reclamation and certification of refrigerant reclaimers 

since 1993. The U.S. has seen an increase in the reclamation of HCFC refrigerants, but a decline in 

the amount of CFC refrigerants reclaimed due to the phase-out of the manufacture of CFCs in the U.S. 

Care should be taken to not cross-contaminate recovered refrigerant. Refrigerants that are combined 

after recovery, such as hydrocarbons with CFC refrigerants, will require separation (normally via 

distillation) prior to reclamation. High costs and the lack of availability of separation facilities 

provide disincentives to the proper recovery of refrigerant. 

11.5.2 Destruction 

During the past four years, since the 2006 Assessment, increased interest in the potential 

environmental benefits of destruction of ODS refrigerant banks has occurred. This is due in part to 

the recognition of environmental benefit gained from the potential ozone and climate benefits from 

the avoided emissions of ODS still remaining in refrigeration and air conditioning equipment worldwide. As a result of these benefits, global carbon trading markets have emerged that might provide 

incentives for early retirement of “banks” of ODS in equipment. There is potential for this equipment 

to be retired or replaced with more energy efficient equipment with lower refrigerant charge sizes. 

ODS refrigerants (specifically CFCs) have high GWPs in addition to their ozone impacts. The 

destruction of ODS banks has the potential to earn carbon credits through global carbon markets, 

broadly divided into the compliance market and the voluntary market. The compliance market for 

GHGs is based on a legal requirement where, at an international (i.e., Clean Development Mechanism 

or CDM) or national and regional level (i.e., European Union Emission Trading Scheme of EU ETS), 

those participating countries and/or states must demonstrate that they hold the carbon credit 

equivalents to the amount of GHGs that they have emitted in order to meet their GHG reduction 

targets or commitments. 
178 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Presently, the voluntary market operates outside of the compliance market where individual 

companies or organisations voluntarily commit to actions and projects to offset their GHG emissions.7

Currently, only the voluntary carbon market has established standards for ODS destruction as carbon 

offsets projects. To date, there are three voluntary standards that recognise and/or have established 

project protocols to provide carbon credits for ODS destruction. Two installation types are available 

to destroy CFCs: 

(1) Public or commercial installations are accessible, in return for payment. These installations are 

often capable of treating several families of chemical products; and 

(2) Private facilities that are designed for the internal needs of ODS manufacturers. These facilities 

are not always adapted to the needs of outside groups. Normal conditions where recovery, recycling, 

and reclamation are prevalent should lead to fairly low requests for destruction in the refrigeration 

industry. This is especially the case where the demand for CFCs will remain high. A need for 

destruction facilities may be created in instances where regulations forbid the use or export of CFCs. 

The general method of destruction is based on incineration of refrigerants and on scrubbing 

combustion products that contain particularly aggressive acids, especially hydrofluoric acid (HF). 

Mainly, their resistance to hydrofluoric acid limits the number of usable incinerators. CFCs, and more 

particularly halons, burn very poorly. In order to be incinerated, they must be mixed with fuels in 

specific proportions. 

Belgium, Brazil, Finland, Japan and Switzerland possess the rotary kiln incineration technology to 

destroy CFC’s, halon, and HCFC’s. These incineration facilities do accept substances for destruction 

from outside countries. Currently, there is little experience with rotary kiln incineration within North 

America. These facilities are expensive to build, maintenance costs are high, and the expense is 

usually only justified where a variety of hazardous wastes must be destroyed. 

Destruction is a viable alternative for handling unwanted banks of refrigerants. There is currently a 

lack of commercially available companies that destroy refrigerants. As A5 countries start their 

phaseout programs, commercial opportunities for destruction may become available. Australia, 

United States, and Japan currently have the capacity to destroy recovered ODS. However, this trend 

appears to be changing with increased interest in both voluntary and regulatory ODS destruction 

initiatives. 

11.6 Equipment Design and Service 

Refrigerant emissions from cooling systems must be minimised to protect the environment. 

Fortunately, conservation is consistent with good functioning and efficiency of air-conditioning and 

refrigeration systems. Cooling systems are designed as sealed units to provide long term operation. 

Conservation is affected by the design, installation, and service of the refrigerating system. 

Guidelines and standards are being updated with consideration to environmental matters and 

improved conservation. 

Conservation is defined by an emission rate, which can be measured and limited. Cooling system 

manufacturers have defined minimum tightness requirements to guarantee permanent operation during 

defined periods. The American Society for Testing and Materials (ASTM) E 479 "Standard Guide for 

Preparation of a Leak Testing Specification" serves as a manufacturer's reference document. The 

standard has a large influence on the maximum allowable leakage flow for a cooling system based on 

the period during which the system must operate without refrigerant recharge. The refrigerant 

 

7

 In the United States, the state of California plans to pursue a compliance market that would accept credits 

generated from a voluntary carbon market that includes credits for ODS destruction projects. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 179

quantity may be lost by leakage during this period without significantly affecting the operational 

efficiency of the system. 

11.6.1 Design 

Every attempt should be made to design tight systems, which will not leak during the life span of the 

equipment. The potential for leakage is first affected by the design of the system; therefore, designs 

must focus on minimising the service requirements that lead to opening the system. Manufacturers 

select the materials, the joining techniques, and service apertures. They also design the replacement 

parts and provide the recommended installation and service procedures. Manufacturers are 

responsible for anticipating field conditions and for providing equipment designed for these 

conditions. Assuming that the equipment is installed and maintained according to the manufacturer's 

recommendations, the design and proper manufacturing of the refrigerating system determines the 

conservation of the refrigerant over the intended life of the equipment. 

Among recommendations for conservation, leak tight valves should be installed to permit removal of 

replaceable components from the cooling system. The design must also provide for future recovery, 

for instance, by locating valves both at the low point of the installation and at each vessel for efficient 

liquid refrigerant recovery. 

11.6.2 Charge Minimising 

Minimising the refrigerant charge will also reduce the quantity of possible emissions that could be 

emitted during catastrophic leak events. Historically, little attention has been given to the full charge 

of equipment, thus, its quantity is not often known (except for small equipment in which the units are 

shipped charged with refrigerant from the original equipment manufacturer). It should be noted that 

there are negative effects of charge minimisation, for example the system may be more sensitive to a 

charge deficit leading to an increase in energy consumption.. There is a balance to ensure good 

efficiency despite minor leakage and reduced direct emissions. 

Overcharging of equipment is common, as the amount of refrigerant contained in refrigerant receivers 

is not always known. Refrigerant receivers are equipment components that contain excess refrigerant 

that migrates through the system as a result of changes in ambient conditions. For such equipment, 

field charging is often continued until the evaporator supply is considered satisfactory. Without the 

check of weighing the charge, installation could be overfilled with two harmful consequences: (1) a 

potential release of refrigerant, and (2) the possibility of transferring the entire charge into the 

receiver. The receiver-filling ratio, therefore, has to be limited during nominal operation, and an 

inspection tool (indicator, level, etc.) must be provided. 

11.6.3 Installation 

Proper installation of refrigerating systems contributes to the proper operation and conservation 

during the useful life of the equipment. Tight joints and proper piping materials are required. Proper 

cleaning of joints and evacuation to remove air and non-condensable will minimise the future service 

requirements. Proper charging and weighing techniques, along with careful system performance and 

leak checks, should be practised during the first few days of operation. The installer should also seize 

the opportunity to find manufacturer defects before the system begins operation. The installation is 

critical for maximum conservation over the life of the equipment. 

11.6.4 Servicing 

Service must be improved in order to reduce emissions. Such improvement, however, depends in part 

on the price end-users agree to pay, as emission reduction has always proved, so far, more expensive 

than topping-off cooling systems with refrigerant. It is necessary to make end-users understand that 
180 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

their previous practice of paying to top-off systems must cease, and those funds must be spent on 

improved maintenance. It is to be noted that such a step has already been taken in some cases, 

especially in countries like the U.S. where an annually increasing tax on the quantities of ozonedepleting refrigerants that remain in stock at the end of the calendar year makes conservation or 

conversion to ozone-friendly refrigerant alternatives more cost-effective. 

Technician training is essential for the proper handling and conservation of refrigerants. Such 

training should include information on the environmental and safety hazards of refrigerants, the 

proper techniques for recovery, recycling and leak detection, and local legislation regarding 

refrigerant handling (if applicable). 

Refrigerating systems must be tested regularly to ensure that they are well sealed, properly charged, 

and operating properly. The equipment should be checked in order to detect leaks in time and thus to 

prevent loss of the entire charge. During maintenance and disposal of the system, refrigerant should 

be isolated in the system or recovered. 

The technician must study the service records to determine history of leakage or malfunction. The 

technician should also thoroughly check for leaks and measure performance parameters to determine 

the operating condition of the cooling system. The technician will want to determine the best location 

from which to recover the refrigerant and assure that proper recovery equipment and recovery 

cylinders are available. The existence of a maintenance document enables the user to monitor 

additions and removals of refrigerant with recovery as well as the searches and repairs of leaks. 

11.6.5 Reduction of Emissions through Leak Tightness 

Leak detection is a basic element, both in constructing and servicing cooling equipment, as it makes it 

possible to measure and improve conservation of refrigerant. Leak detection must take place at the 

end of construction by the manufacturers, at the end of assembly in the field, and during regularly 

scheduled maintenance of equipment. 

There are three general types of leak detection: 1) Global methods indicate that a leak exists 

somewhere, but they do not locate the leaks. They are useful at the end of construction and every 

time the system is opened up for repair or retrofit; 2) Local methods pinpoint the location of the leak 

and are the usual methods used during servicing; 3) Automated performance monitoring systems 

indicate that a leak exists by alerting operators to changes in equipment performances (see Appendix 

1). 

Governments should take a sector based approach aimed at adopting service requirements that reduce 

use and emissions of ODS. The major refrigeration and air-conditioning sectors include the 

following: 

Refrigeration sectors include: 

• Residential applications-refrigerators, freezers, window air-conditioners 

• Commercial refrigeration-convenient stores, warehouses, supermarkets, and grocery stores 

• Large size refrigeration-industrial process refrigeration systems used in an array of 

manufacturing and food processing applications 

• Transport refrigeration-refrigerated transport vehicles 

• Unitary air-conditioning-residential and light commercial air conditioners and heat pumps 

• Chiller/comfort cooling application-chillers 

• Mobile air conditioners. 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 181

Various countries have demonstrated improvement in the air-conditioning and refrigeration equipment 

manufactured over the past few years. The new equipment has been designed to be tighter than airconditioning and refrigeration equipment previously manufactured. Existing appliances have often 

been modified with new devices, such as high-efficiency purge devices for low-pressure chillers that 

have significantly lowered refrigerant emissions. Design changes have been made in response to 

growing environmental, regulatory, and economic concerns associated with refrigerant emissions. 

For instance, research performed by the U.S. EPA indicates that the reduction in leak rates in the U.S. 

has been most dramatic in comfort cooling chillers. Leak rates have been lowered from between 10 

and 15% per year, to less than 5% per year in many cases, through design changes. 

In the Netherlands, the results of some earlier monitoring projects have been previously reported. 

Those earlier studies involved a large sample of transport refrigeration units and commercial 

refrigeration systems. Earlier refrigerant emissions were compared over time for units built before and 

after introduction of the Dutch regulatory program. Comparison found that in the case of transport 

refrigeration, the refrigerant emission rate was reduced from an average of 6% to 3% of the charge per 

year. For selected commercial supermarket systems the average emission rate was reduced from 15% 

of refrigerant charge to 3%, on an annual basis. In another monitoring project, large refrigerating 

systems (average charge of 2 metric tonnes) up to 10 years old were inspected during 1994-1996. The 

average annual leakage rate was found to be 8.6%. Information on similar but older equipment built 

over the period 1986-1992 indicated an average leakage rate of 12.2% The report concluded that the 

reductions in refrigerant losses experienced for the more recently constructed systems was attributable 

to the more stringent technical requirements specified under the 1994 Regeling 

Lekdichtheidsvoorschriften Koelinstallaties (RLK) technical requirements for refrigeration 

equipment. 

More recent monitoring data has been gathered from the detailed National Survey of Refrigerant 

Flows NOKS study which was conducted for the government to investigate the volumes of CFCs, 

HCFCs, and HFCs being used throughout the country for refill purposes in all application sectors 

(excluding auto air-conditioning and marine installations). Relating this data directly to refrigerant 

emissions, it was concluded that the average annual leakage rate for the reference year 1999 was 4.8% 

(equivalent to approximately 615 tonnes nation-wide). Furthermore, the NOKS study revealed that 

the emissions were attributable to only 8% of the installations, and 92% had no emissions that year 

/IEA02/. 

11.7 Direct Regulation as a Means of Refrigerant Conservation 

Refrigerant emissions are already regulated in a number of countries, mostly as a component of the 

implementation of the CFC phase-out. Government actions such as introducing and enforcing direct 

regulations or legislation are necessary to ensure refrigerant conservation. Existing regulations include 

service technician certification, required equipment service and disposal practices, leak tightness 

requirements, restrictions on the sales of refrigerants and certification schemes for service companies. 

For purposes of refrigerant conservation, direct regulation may include governmental efforts 

establishing the following: 

- Mandatory service and disposal practices for air-conditioning and refrigerating equipment 

- Certification programs for air-conditioning and refrigerating equipment and 

recovery/recycling equipment 

- Required training and/or operator certification programs for service technicians 

- Restrictions or limitations on who can purchase or sell ODS refrigerants 

As is the case for financial incentives, care should be taken to set standards that maximise 

conservation without being unduly burdensome. Direct regulations establish "floor" standards and 

practices across industry, and training and/or certification requirements increase general knowledge of 

both how and why to contain the refrigerant. However, these regulations are often less flexible than 
182 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

financial incentives, and more difficult to develop and enforce, given the large quantities and wide 

distribution of air-conditioning and refrigerating equipment. 

Article 2 countries have taken a number of steps aimed at reducing emissions of ODS refrigerants via 

direct regulation. Some regulations include the restriction of the supply of refrigerants through limits 

in imports and sales. As well as requirements for emissions reduction practices, during the service and 

disposal of appliances, and mandating the recovery, recycling, and reclamation of used refrigerant. 

Such restrictions may also have negative impacts, such as the creation of illegal markets for 

refrigerants, fraudulent business practices by service companies, refrigerant distributors, and 

appliance recyclers. The financial impact of enforcing such regulations presents another possible 

negative impact. Such regulations should not be attempted unless the governmental body is willing to 

invest in the long-term enforcement of the regulations and strict prosecution of those who violate such 

regulation. 

Countries with established markets have similar national programs and policies in place for the 

recovery, recycling, and reclamation of refrigerants, but individual approaches to organisation and 

control mechanisms, responsibility levels, regulatory legislation, financing arrangements, and 

operating procedures vary considerably from one country to another. 

In addition to phasing out production of ODS under the Montreal Protocol, governments chose to 

reduce ozone-depletion by strongly encouraging conservation through different means. In the first 

years, research and development (R&D) programs were funded to identify emission sources and 

develop conservation measures. Other R&D programs were developed to evaluate efficient recovery, 

recycling, and reclamation equipment. Governments also worked with industry groups to develop 

recovery techniques, and establish standards for the recovery and reuse of ozone-depleting 

refrigerants. 

Information dissemination was another means used to educate the public on the environmental health 

and safety issues associated with ozone-depletion. These efforts created a general knowledge of both 

how and why measures should be taken to contain used refrigerant; thus, these efforts improved 

conservation where ignorance of environmental issues was the primary problem. 

Direct regulation also became a point of emphasis for governments. Many governments improved 

conservation through direct regulation. Governments have found that adoption of industry standards 

and R&D results are easily incorporated into regulation as a means of mandating refrigerant 

conservation. While governments have found direct regulation to be a successful means of 

conservation, it requires a strong commitment to legal or financial enforcement incentives in order to 

reach significant results. 

11.7.1 Financial Incentives 

Financial incentives can encourage conservation by making emissions more costly for users or by 

making conservation efforts financially beneficial. They may include sales taxes on refrigerants at the 

point of purchase or import across the country’s border, deposit-refund schemes to discourage 

disposal of refrigerant containers, and/or tax breaks for investing in recovery/recycling equipment or 

other refrigerant conservation technologies. 

In the U.S., the manufacture or import of virgin CFCs is prohibited. In addition, the U.S. annually 

increases the CFC-excise tax that has been effective in increasing conservation of CFC refrigerants 

and making retrofits to lower ozone-depleting substances more financially appealing. The tax when 

combined with the phase-out of the manufacture of CFCs has forced an increase in the recycling and 

reuse of used CFC-refrigerants. This increase in the recycling and reuse of used refrigerant has 

addressed a significant source of emissions by inflating the costs of imported CFCs; thus, making it 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 183

less expensive to reuse CFCs or retrofit equipment to refrigerants with lower ozone-depleting 

potentials than to buy and use imported CFCs. 

Deposit-refund schemes involve collecting a deposit when a product is purchased and paying a refund 

when the used product is returned. The refund serves as an incentive to the user to collect and return 

used refrigerants. The deposit not only finances the refunds, but also encourages more careful 

handling of the product by increasing the cost of new refrigerant. Two issues must be faced in 

establishing a deposit-refund system: (1) how (or whether) refrigerants are traced back to the original 

manufacturer for collection of the refund and (2) how refunds for the bank of refrigerants in existing 

equipment, for which no deposit was collected, can be financed. Industry-sponsored deposit-refund 

schemes in Australia, Denmark and France resolved these issues by setting up a centralised fund for 

deposits. 

Tax breaks for investing in refrigerant conservation equipment and technologies are another 

government means of coercing conservation. Since tax breaks that are linked to specific technologies 

have the potential to limit technology that enters that marketplace, they can leave the market less 

flexibility than either sales taxes or deposit-refund schemes. Care should be taken to set taxes, tax 

breaks, and deposit-refund amounts at levels that will maximise conservation without being unduly 

burdensome. In addition, governments using financial incentives must work to prevent the rise of a 

black market for untaxed, and therefore, less expensive refrigerant. Left unchecked, such a market 

will eventually undermine the environmental incentives implemented by the incentive. In order to 

limit the extent of black market sales, such tax efforts should not be attempted without a strong 

enforcement component with the power to fine and or imprison violators. 

Governments may find that financial incentives are easier and more flexible to develop than direct 

regulations. Financial incentives allow markets to find the most cost-effective conservation measures 

and maintain the incentive to innovate. Moreover, governmental financial incentives become more 

important as refrigerant prices drop. Such is the case for HCFCs and HFCs in many Article 2 

countries, and for CFCs in many Article 5 countries, because higher refrigerant prices tend to 

encourage conservation, while lower prices tend to discourage it. However, it can be difficult to set 

financial incentives at a level that encourages conservation without being unduly burdensome. 

Financial incentives will be undermined if a black market for imported refrigerants is allowed to 

operate. 

 

11.7.2 Required Service Practices and Leak Tightness 

In the European Council (E.C.) Regulation no. 2037/2000 on substances that deplete the ozone layer 

/EC00/, the E.C. requires that all precautionary measures practicable shall be taken to prevent leakage 

of CFCs and HCFCs; however, the member states may define their own minimum qualification 

requirements for the servicing personnel involved. An annual leak tightness inspection is made 

mandatory for installations containing CFCs or HCFCs. Three national programs are summarised 

below, but regulations also exist in other European countries such as Denmark, Germany and Sweden. 

The Netherlands described the conditions for the leak tightness of systems in a decree of December 

18, 1994 /DR94/. This text is characterised by detailed requirements for materials and components, 

design, installation, machinery rooms, tests and maintenance, inspection. It contains requirements 

dealing with the maintenance, the leak tightness controls, and the installation inspection depending on 

the charge of refrigerant. The occurrence of leak tightness is also specified: once a year for charges 

under 3 kilograms, once every 3 months for more than 30 kg, once a month for more than 300 kg. 

Machinery rooms are mandatory for charges of more than 300 kg, and an area monitor is required 

when the charge is more than 1,000 kg. The area monitor sensitivity (100 ppm), the minimum 

number of probes (5), and the installation of the probes (at least one at floor level, at least one in the 

ventilation exhaust duct) are specified. Certified operators who are equipped with leak detectors of 

five ppm sensitivity perform the leak tightness tests. Before commissioning new installations or 
184 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

changing refrigerant, leak tightness test must be performed at the maximum working pressure of the 

equipment. 

The United Kingdom Environmental Protection Act of 1990 mandates several measures for the 

conservation of CFC, HCFC, and HFC refrigerants. These include a prohibition on venting 

refrigerant during service or decommissioning of systems, a prohibition on adding refrigerant to a 

leaking system before thoroughly examining the system to locate and repair the leak, a requirement to 

use a vacuum pump to evacuate moisture and non-condensables from a system before adding 

refrigerant, a requirement to use a refrigerated purge unit (as opposed to manual purging) to purge 

non-condensables from the system, and a general requirement to limit emissions during a number of 

procedures for system servicing and operation. 

The Clean Air Act Amendments of 1990 mandate leak repairs, In the U.S., refrigerant emissions are 

controlled by direct regulations requiring recovery, recycling, and reclamation. The U.S. has also 

created regulations mandating repairs of equipment that leak above allowable rates. U.S. regulations 

require that appliance manufacturers provide a service aperture to expedite recovery of refrigerant. 

As for servicing, before repairing or disposing of air-conditioning and refrigeration equipment, 

technicians must recover the refrigerant using government approved refrigerant recovery equipment. 

The percentage of refrigerant that must be recovered or the level of evacuation that must be achieved 

varies depending upon the type of equipment being serviced. For leak repair, the U.S. regulations 

require owners of equipment containing charges of more than 50 pounds to either repair, retrofit, or 

replace their refrigeration and air-conditioning equipment when they leak in excess of an applicable 

maximum allowable rate. These maximum annual allowable rates are 35% of the charge for 

commercial and industrial refrigeration and air-conditioning applications and 15% for other 

applications. To track leak rates, owners of air conditioning and refrigeration equipment with more 

than 50 pounds of charge must keep records of the quantity of refrigerant added to their equipment 

during servicing and maintenance procedures. 

11.7.3 Restrictions on the sales and imports of ODSs 

The U.S. has limited the sales of refrigerant to technicians who have been certified in order to 

improve the level of awareness against refrigerant emissions. In addition to this sales restriction, the 

government has placed conditions on the manufacturers of substitute refrigerants. New non-ODS 

refrigerants, which replace CFCs, must be authorised for specific industry sectors and end-uses. The 

government also mandates that manufacturers of new refrigerants place unique fittings on containers 

to prevent unintended mixing of different refrigerants, and subsequent emissions resulting from the 

mixtures. 

The U.S. also restricts the amount of imported ODSs into the country. Only used class I ODSs 

(primarily CFCs, halons, and methyl bromide) are allowed for U.S. import. The U.S. has banned the 

import of virgin ODS, with the exception of pre-approved essential uses. Prospective importers must 

petition the U.S. EPA for approval prior to transport from the country of origin. 

Several countries have implemented regulations that require customs officers to complete ODS 

training programs. The training of customs officers in detection and identification methods helps to 

control trade in ozone-depleting substances. For instance, the Democratic Republic of Congo and 

Jordan have recently both taken significant steps to increase their phase-out of ozone depleting 

substances. These countries now require training programs for customs officers as well as the 

technicians that handle the refrigerant. Other countries such as Oman, provide training workshops for 

their customs officers in order to raise the level of awareness regarding the dangers of ODS and 

methods of refrigerant conservation. 

The training of customs officers and identification of refrigerants are considered as the most important 

part of CFC phase-out program in the countries from Eastern Europe, Caucasus and Central Asia. For 

instance 115 customs officers have been trained and equipped with Refrigerant Ultima Identifier in 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 185

Armenia. In Republic of Tajikistan 98 customs officers have been trained in detection and 

identification methods and 30 check-points have been equipped with Neutronics RI - 2002PA 

identifier. The same figures for Uzbekistan are 301 trained customs officers and 21 units of portable 

identifier ID 1000 used in the country. In Republic of Georgia a special laboratory equipped with 

Complete Gas chromatograph and Tasco TA400 refrigerant analyser helps customs officers to identify 

CFCs, HCFCs, HFCs and a wide range of their blends. 

Restrictions are also placed on new refrigerant blends, which must be authorised by the U.S. EPA 

prior to introduction into interstate commerce. Manufacturers of refrigerant blends that are 

anticipated to replace ODSs are required to submit data to EPA on the health and safety of such 

substitutes before they can be legally sold in the U.S. 

11.8 End-of-life 

Safe disposal requirements should mandate disposal of ODS components in residential appliances 

such as refrigerant and foam. Many household refrigerators and freezers produced prior to 1994 rely 

on CFC refrigerants that destroy the earth’s protective ozone layer, which in turn leads to adverse 

human and environmental health effects (see text box). After 1996, most newly manufactured 

household refrigerators and freezers contain hydrocarbon refrigerants or ozone friendly refrigerants 

(HFCs). Similarly, oil in the compressor is likely to be contaminated with refrigerant, be it CFC or 

HFC, so it too must be treated carefully. In addition, the foam blowing agents in most in-use 

refrigerators/freezers also use ozone depleting substances. Ultimately, if these foams are not properly 

recovered from appliances and properly disposed, additional ODS will be released to the atmosphere, 

leading to further destruction of the ozone layer. Some of the newest refrigerators/freezers use HFC 

blowing agent, which can lead to GHG emissions if not properly recovered at end of life. Further, 

raw materials that make-up refrigerators and freezers—including steel, plastic, glass, and rubber—can 

all be recycled to reduce the amount of waste that would otherwise be put in a landfill and save energy 

that would otherwise be required to produce virgin materials. Finally, some chest freezers 

manufactured prior to 2000 may contain a mercury switch. Mercury is toxic and causes a variety of 

adverse health effects, including tremors, headaches, respiratory failure, reproductive and 

developmental abnormalities, and potentially, cancers. Also, older appliances may contain PCB

capacitors. PCBs can lead to adverse effects ranging from minor skin irritations, to reproductive and 

developmental abnormalities, to cancers in humans and wildlife. 

Efforts should be taken to make certain that companies involved in the disposal chain are not allowed 

to destroy. 

11.9 Examples of Conservation Approaches 

11.9.1 Africa 

The refrigeration and air-conditioning sector plays a vital role in many of Africa’s economies. The 

predominant sectors in these economies are the agriculture, tourism, and fishing industry. As a result, 

refrigeration is necessary to preserve perishable foodstuffs that are both exported abroad and are 

necessary for local consumption. Likewise, the tourist industry increases the demand for airconditioning, as visiting tourists prefer comfortable environments. 

There has been a reasonable reduction in the consumption of ODS in most African countries. Certain 

countries have undertaken measures to put a partial or total ban on sales of CFCs. Others have put 

regulations in place to control imports of new CFCs and CFC-based equipment. It is obvious that 

existing refrigeration equipment will need servicing and maintenance for a long period of time. 

However, there is not enough training of refrigeration technicians. In Africa, a well-developed 

educational program for technicians is non existent, thus, those employed in the refrigeration industry 

do not receive proper instruction needed to comply with standards Examples from other countries 
186 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

have shown that well-trained technicians could reduce the consumption of CFCs in the refrigeration 

sector by up to 40%. The other main problem for Africa in its bid to phase-out the CFCs is the influx 

of used refrigeration equipment and cheap CFCs, some of which are obtained through the Black 

Market. 

Many countries, including but not limited to Benin, Chad, Egypt, Mozambique, Uganda, and 

Zimbabwe, have established refrigerant recovery and recycling programs that train technicians and 

make refrigerant recovery equipment and service equipment available. These national programs are 

responsible for the phase-out of tonnes (ODP-weighted) of CFCs from stationary and mobile sources. 

For example, Kenya has banned service on refrigeration and air-conditioning equipment by anyone 

other than government certified service technicians. The government has also established centralised 

refrigerant recycling stations. The government has promoted the availability of portable refrigerant 

recovery units that are affordable for service technicians. The refrigerant recovery units were donated 

to select workshops that have trained technicians on staff. The government reserves the right to 

repossess the equipment and ban the technicians from the trade if it is found that good service 

practices are not employed. 

Ghana ratified the Montreal Protocol on 24 July 1992. A Country Program was submitted at the 8th 

meeting of the Executive Committee in October of the same year. The 8th meeting of the Executive 

Committee had approved US $328,000 for a program to improve refrigeration servicing and 

maintenance, Ghana’s program looked to establish a National Committee for Improved Refrigeration 

Practices, technical assistance and delivery of recovery and recycling machines, all to be implemented 

by UNDP. Ghana’s RMP statistics find that the most important consumer of CFCs in the country is 

the domestic sector. The estimated number of domestic refrigerators was reportedly 1 million in 2000, 

and had increased by 30-40% in 2003. Total consumption of CFCs from repair and maintenance of 

domestic refrigerators amounts to about 20 tonnes per year. 

In 1996, 3,000 trained technicians were already trained in best practices. An additional 600 

technicians have been trained in safe handing, and retrofitting to hydrocarbons. However, 

certification of technicians is not mandatory in Ghana to practice recovery and recycling activities. 

The recovery equipment provided under the RMP, have been allocated to workshops according to 

location, security and quantity of refrigeration used. To improve recovery efforts, the RMP has 

established an incentive program to encourage refrigeration end-users to replace or permanently 

retrofit their existing ODS based equipment. In Ghana hydrocarbons are significantly cheaper than 

CFCs and HCFCs, as hydrocarbons are produced in Ghana and also imported from Lebanon. In view 

of the prevailing economic conditions, the dominance of the domestic sector, the negligible scrap rate 

of appliances, and the old age of imported vehicles and other refrigeration equipment, phase-out of 

ODS proves to be a fairly difficult task. 

Senegal ratified the Montreal Protocol in May 1993 along with the London Amendment; the 

Copenhagen Amendment and the Montreal Amendment were ratified in August 1999. to assist 

Senegal UNEP provided training for trainers in good refrigeration practices, followed by training of 

technicians by these trainers under a project approved by the 11th meeting of the Executive 

Committee. Since 2001, a Refrigeration Management Plan (RMP) has been implemented with the 

assistance of UNIDO, Switzerland and UNEP. 

The remaining users of CFC in Senegal are private companies servicing domestic, industrial and 

commercial refrigeration systems. The most prevalent barrier to retrofit remains the humid climate of 

Senegal. The hygroscopic nature of ester oil, not to mention its high price, makes it difficult to 

prevent humidity entering the system resulting in corrosion and clogging problems. 

Under a training program implemented by UNEP, a total number of 140 technicians have been trained 

in four workshops, addressing issue like these. Previous standard practices like flushing with CFC 

have been replaced by using nitrogen or compressed air. Charging refrigerants is now measured with 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 187

manifolds and brazing joints is more common now than using hoses thereby reducing the likelihood 

of leaks. Additionally a total of 40 recovery units have been made available) as well as, leak 

detectors, vacuum pumps, empty cylinders, scales, manifolds and other tools were provided, supplied 

through UNIDO. 

CFC-12 remains relatively inexpensive, posing a great threat to effective regulatory control. Increases 

in the illegal smuggling of CFCs, originating in Eastern Europe, continues to occur. Therefore, 

continued training of Customs officials is necessary. 

Most countries have established national programs to recover and reuse refrigerants. Although there 

is great potential for the recovery and recycling of CFCs in low volume consuming African countries, 

the low price of virgin refrigerant has decreased the incentive to recover refrigerant. There has also 

been a shortage of recovery and recycling equipment, as the cost is considered too expensive for the 

majority of the common workshops. It is expected that that suitable legislation, regulations, and 

recovery and recycling schemes currently under development will create the much needed incentives 

for recycling. 

11.9.2 South America 

The Brazilian government has established a refrigerant conservation program that banned the use of 

disposable refrigerant cylinders. The Brazilian Association of Domestic End Commercial Appliances 

has certified an estimated 1500 service shops, employing nearly 3000 service technicians. It is 

estimated that these certified shops recycle nearly 3.5 MT of CFC-12 per month from the domestic 

refrigeration and air-conditioning sector. 

Through a National CFC Phaseout Plan, approved in July 2002 by the Multilateral Fund, the Brazilian 

government is planning to establish eight refrigerant reclamation centres within the next two years. In 

certain regions of the country, recycling and reclamation activities have begun in advance of the full 

implementation of the National CFC Phaseout Plan. The national plan anticipates the training of 

35,000 refrigeration service technicians and the distribution of refrigerant recovery equipment to the 

technicians. The national plan includes efforts to establish a CFC recovery program in conjunction 

with the installation of the refrigerant reclamation centres. In addition, Brazil has a destruction 

facility that accepts contaminated refrigerant for incineration by rotary kiln. 

Colombia ratified the Vienna Convention in 1990, the Montreal Protocol and its London Amendment 

in 1993, the Copenhagen Amendment in 1997, the Montreal Amendment in 2003 and the Beijing 

Amendment in 2005. In Colombia, 81% of total CFC consumption can be attributed to the service 

and maintenance of domestic, industrial, and commercial refrigeration systems. With the aid of MLFfunded conversion projects, the number of CFC-based commercial refrigeration units is expected to be 

reduced to about 850,000 by 2007. CFC prices remain high in Colombia however the price of 

alternatives are significantly more expensive. The process of phase-out of ODSs in Colombia 

consisted of a project-by-project approach concentrating on the large CFC consumers such as 

manufacturers of domestic and commercial, conversion projects in medium-sized commercial 

refrigeration units, and finalising projects in the foam and refrigeration sector and starting the 

implementation of the National Phase-out Plan (NPP). Total funds disbursed by the MLF for these 

projects from 1994 to 2004 (without including funds for the implementation of the NPP) amounted to 

US$ 1,112 million. As a result, 1,053 ODP tonnes have been eliminated. Programs within the NPP 

was planned to recover 123.75 ODP tonnes per year, a large part of which was assumed to be 

recycled. Actual amounts recovered during 1998-1999 were 41,9 ODP tonnes and 3,5 tonnes 

recycled. Substantial impediments to the NPP program effected its degree of success. The low price of 

virgin refrigerant in comparison with the costs of recovered substances meant that neither for endusers nor for the servicing workshops there was an economic incentive to recover and to recycle the 

refrigerant. Secondly, the equipment distributed under this project was limited to the recovering of 
188 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

CFC-12 and the type of the machines selected did not take into account the diversity of uses required 

and the different needs of the technicians. 

 

11.9.3 China 

In 2002 China consumed 75% of East Asian share of CFCs and produced almost 100% of the regional 

share. By January 2003, CFC production in China was reduced by 40% and 32 plants were closed and 

dismantled. 

During 1992, China’s State Environmental Protection Agency’s (SEPA) established a motor vehicle 

air conditioning sector program. The program is sets national policies and regulations, including the 

ban on new CFC-based MAC systems in all new vehicles by January 1, 2002; a technical assistance 

program for developing of service and refrigerant recycling standards; establishment of testing 

facilities for motor vehicle air conditioning components and systems; and a new certification system 

and training for the motor vehicle air conditioning industry. 

China is currently seeking financial incentives, such as tax breaks, for refrigerant conservation. Also, 

the government is exploring options for the enforcement of State Environmental Protection Agency 

(SEPA) regulations. China Refrigeration and Air-Conditioning Industry Association (CRAA) 

established the standard: CRAA100-2006 (specifications for fluorocarbon refrigerants. The standard 

is applicable for new and reclaimed refrigerants, and is not applicable for only recycled refrigerants. 

11.9.4 United States 

The United States has seen an increase in the degree of community outreach and has seen the 

implementation of many CFC restricting regulations. There are currently regulations requiring 

technician certification, restriction on sales, mandatory recycling and servicing requirements, and safe 

disposal requirements. Proper retrofit procedures from CFCs to substitute substances have been 

created and distributed by chemical and equipment manufacturers. The U.S. has recognised an 

impediment in its conservation efforts. While the U.S. bans the import of virgin ODSs, the U.S. does 

allow used CFCs to be imported once approved by the government. Such efforts have extended the 

life span of CFC equipment, and have allowed equipment owners to hold off on retiring CFC 

equipment. 

11.9.5 Japan 

The recycling law concluded its first year since enforcement in April 2001, with good results in the 

recovery of CFC and HCFC refrigerants from discarded residential air-conditioners and refrigerators – 

603 metric tonnes of CFC and HCFC refrigerants (467 from air conditioners and 136 from 

refrigerators) were extracted and destroyed in 2001. The amount has continued to rise, reaching 1306 

metric tons (995 from residential air conditioners and 311 from domestic refrigerators) in 2004. 

Recovery of refrigerants from insulators used for refrigerators started in 2004. In a move to accelerate 

recycling, the Japanese cabinet approved an additional bill, requiring automobile manufacturers and 

importers to accept used cars to recycle different parts including CFCs. The law went into effect in 

2003, and added a consumer-recycling fee to the price of each new car sold in Japan. 

With the aim of raising the recovery rate of refrigerants from commercial equipment, the 

Fluorocarbons Recovery & Destruction Law was amended to be effective from October 2006. By this 

law, refrigerant recovery from commercial refrigeration and air conditioning equipment is expected to 

reach a higher level than ever before.
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 189

11.10 Article 5 Issues 

Although the wide range of conditions in Article 5 countries make generalisation difficult, a few 

characteristics emerge across the refrigeration infrastructures that distinguish Article 5 countries from 

those of developed countries. These characteristics argue for the adoption of somewhat different 

strategies for containing and conserving refrigerant in Article 5 countries than are used in developed 

countries. Among these characteristics are: 

- The ambiguous situation on the market of CFC refrigerants. CFCs remain relatively inexpensive in 

most Article 5 countries. In fact, CFC refrigerants are reportedly less expensive than ever in some 

Article 5 countries. On the other hand there are Article 5 countries were CFCs are practically 

unavailable or they are very expensive but very often CFCs are replaced by cheap counterfeited 

refrigerants that causes breakage of cooling systems and accordingly increase of Emissions. This 

decreases economic incentives to conserve CFC refrigerants. In order to succeed, conservation 

approaches must either make efficient use of technicians' time and equipment, or be supported by 

credible government incentives and/or penalties. 

- The relatively low cost of labour compared to recovery equipment. Low labour rates may favour 

conservation approaches that are somewhat more labour-intensive than those historically pursued in 

developed countries. However, technician training and awareness are essential to the success of such 

approaches, especially where preventive maintenance procedures have not been routine in the past. 

Moreover, significant incentives are still necessary for refrigerant conservation because of the low 

cost of CFCs. 

- Weak refrigerant reclamation infrastructures. A well-developed infrastructure for reclaiming 

refrigerant requires large numbers of reusable refrigerant containers, refrigerant purification centres, a 

system for tracking returned refrigerant, and a means of disposing of irretrievably contaminated 

refrigerant. The amount of refrigerant to be recovered in countries using small quantities of 

refrigerant is not likely to justify operation of a centralised reclamation centre. To ensure that 

refrigerant is adequately cleaned before being reused, developing countries may either devote 

resources to developing a reclamation infrastructure or emphasise on-site refrigerant recycling. If 

they choose the latter, screening tests may be used to target severely contaminated refrigerant for 

destruction. Because of the decentralised nature of on-site recycling, its success (in terms of both the 

quantity and quality of the refrigerant recycled) is more difficult to evaluate than that of reclamation. 

Where reclamation facilities are not available, an alternative may be destruction in existing 

incinerators. 

- Lack of scheduled maintenance. In the past, for many Article 5 countries, routine scheduled 

maintenance of air-conditioning and refrigeration equipment has been rare. To successfully implement 

conservation approaches, which rely heavily on regular maintenance, countries should provide 

incentives for such routine scheduled maintenance. 

- Unreliable power, parts, and supplies. In many Article 5 countries, frequent voltage fluctuations 

increase the occurrence of compressor burnouts, which aggravate refrigerant contamination problems 

and discourage refrigerant recycling. The same voltage fluctuations may also damage electrical 

recovery equipment, which in combination with the limited availability of replacement parts, may 

make it difficult to keep such equipment operational. Recent experience has shown the need to adapt 

recovery equipment to the requirements of Article 5 countries (such as extreme climatic conditions, 

lack of spare parts, and higher frailty of electric devices). 

Together, these characteristics have certain implications for refrigerant conservation programs in 

Article 5 countries. Because the ability to recover large amounts of refrigerant in a relatively small 

amount of time increases the cost-effectiveness of recovery, recovery programs may be most effective 

if focused either on equipment with large charge sizes (e.g., chillers or large commercial refrigeration 
190 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

systems) or on large groups of equipment with small charge sizes (e.g., motor vehicle airconditioners). 

For other systems, such as those with small size and widespread ownership (e.g. domestic and small 

commercial refrigerators), experiences indicate that retrofitting and recovery are more difficult to 

implement and that the emphasis should be put on conservation. 

In addition to imposing conservation measures on individual pieces of equipment, countries may 

reduce emissions of CFC refrigerants by reducing the total stock of equipment containing CFCs. This 

may be accomplished by selecting systems that use HCFCs or non-ozone depleting refrigerants when 

installing new equipment or by retrofitting existing systems to use HCFCs or non-ozone depleting 

refrigerants. The high rate of growth in Article 5 countries makes the selection of new equipment 

especially important. Labour intensive retrofits may be attractive in some Article 5 countries due to 

relatively low labour rates. It is important to note that replacement or retrofit of equipment will 

increase rather than decrease CFC emissions if the CFC refrigerant from the old equipment is vented 

rather than recovered. This emphasises the fact that for any refrigerant, the first step to take towards 

conservation is improving the leak tightness of systems. 

There is no shortage of leak detection devices, conservation methods, or recovery/recycling 

equipment available from developed countries /UNE94,95/. However, provision of such equipment 

will not, in itself, guarantee that refrigerant conservation occurs in Article 5 countries. Experience has 

shown that in order to be effective, conservation programs must match equipment with training and 

incentives to use the equipment. These incentives may be financial (e.g., deposit-refund systems 

similar to those used in Australia and France), professional (building on technicians' pride in 

completing training and in using the most advanced equipment and techniques), or environmental 

(showing technicians that they have the power to help heal the ozone layer). The Refrigerant 

Management Plans (RMPs) which focus on A5 countries consuming low volumes of ODS in critical 

refrigerant sectors include these different aspects /UNE98/. 

In order to meet the target of the CFC phase-out, emphasis should be placed not only on replacing 

CFCs in new and existing equipment, but also on refrigerant conservation through recovery, 

recycling, reclamation and leak reduction. 

11.11 References 

/ARI 700/ ARI Standard 700-2004: Specifications for Fluorocarbons Refrigerants. Air Conditioning and 

Refrigeration Institute, Arlington, VA. 

/ARI 740/ ARI Standard 740-1998: Performance of Refrigerant Recovery/Recycling Equipment. Air 

Conditioning and Refrigeration Institute, Arlington, VA. 

/ARI 94/ Handling and reuse of refrigerants in the United States. April 94 draft published by ARI. Air 

Conditioning and Refrigeration Institute, Arlington, VA. 

/ASH92/ ASHRAE guidelines 3-1990 and 3a-1992. Reducing Emission of Fully Halogenated 

Chlorofluorocarbon (CFC) Refrigerants in Refrigeration and Air Conditioning Equipment and 

Applications. 

/ASH15/ Safety Code for Mechanical Refrigeration. Standard ASHRAE 15-2004. 

/BEN01/ Bennett M. Refrigerant Reclaim Australia. IIR Conference on Refrigerant Management and 

Destruction Technologies of CFCs, Dubrovnik, Croatia, Aug. 2001. 

/BU01/ D. Butrymowicz. Refrigeration and air conditioning sector in Poland. Communication during the 

Budapest TOC meeting, April 2001. 

/CAA05/ Final Rule Summary: Complying with the Section 608 Refrigerant Recycling Rule. U.S. 

Environmental Protection Agency. 6205-J, 2005 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 191

/Clo93/ D. Clodic and F. Sauer: Result of a test bench on the performances of refrigerant recovery and 

recycling equipment. ASHRAE Transactions. Denver. Annual Meeting. June 1993. 

/Clo94/ D. Clodic and F. Sauer for the French Association of Refrigeration (A.F.F.), Paris: The Refrigerant 

Recovery Book. 1994 ASHRAE Edition.(Vade-Mecum de la Récupération des CFC. 1993 PYC 

Edition). 

/Clo98/ D. Clodic. Zero Leaks. ASHRAE Edition. 1998. (Zéro Fuites. 1997 PYC Edition). 

/DES 92/ Ad-hoc Technical Advisory Committee on ODS Destruction Technologies. UNEP, May 1992. 

/DR94/ Order of the Minister of Housing, Spatial Planning and Environment, on regulations on leak-free 

refrigeration equipment (1994 Order on leak-free refrigeration equipment). The Netherlands, June 

1995. 

/EC00/ European Council (E.C.) Regulation no. 2037/00 of 29 June 2000 on Substances that Deplete the 

Ozone Layer. Official Journal of the European Communities no. L244. 

/FD92/ French Decree no. 971271 of 7 December 1992, J.O. of 12 December 1992. 

/Hot94/ S. Hotani and N. Sawada: References about the decomposing CFCs by mean of an inductively-coupled 

radio-frequency plasma. 

/IEA02/ Refrigerant Management Programs: Refrigerant Recovery, Recycling and Reclamation. IEA Heat 

Pump Center. The Netherlands, April 2002. 

/ISO/ ISO 11650: Performance of Refrigerant Recovery and/or Recycling Equipment. 

/Kauf92/ Kauffman R.E. Chemical Analysis and Recycling of Used Refrigerant from Field Systems. ASHRAE 

Transactions 1992. 

/KMO98/ Evaluieringsrapport for perioden 15.4.92 till 31.12.97. 1998. 

/Manz 91/ K. MANZ: How to handle multiple refrigerants in recovery and recycling equipment. ASHRAE 

Journal. April 1991. 

/Miz94/ K. Mizuno: Technologies for destruction of ODS in Japan. UNEP Technology and Economic Panel on 

ODS destruction workshop. October 20-21, 1993, Washington D.C. 

/NIR/ National Institute for Resources and Environment AIST, MITI: Ò Development of CFCs destruction 

system using radio-frequency plasma. 

/RIN98/ F. Rinne : Substitution von R-22 in gewerblichen Kälteanlagen und Kühlmöbeln. XX FKW Seminar. 

Hannover, Germany, June 9, 1998. 

SAEJ 1990 Extraction and Recycle Equipment for Mobile Automotive Air Conditioning Systems. Society of 

Automotive Engineers, Warrendale, PA. 

SAEJ 1991 Standard of Purity for Use in Mobile Air Conditioning Systems. 

Society of Automotive Engineers, Warrendale, PA. 

/Sau 95/ Recovery and containment of refrigerants in France. IIF. The Hague. 1995. 

U.L. 1963 standard: Refrigerant Recovery/Recycling Equipment. Standard for Safety. Underwriters Laboratories 

Inc, Northbrook, IL. 

/UNE94/ Preliminary list of Manufacturers of Refrigerant Recycling, Recovery and Reclaim Equipment. UNEP 

IE, 1994. 

/UNE94/ Recovery and Recycling. Case Studies. UNEP IE, June 1994. 

/UNE98/ Refrigerant Management Plan. UNEP, IE, 1998. 

/VAN98/ Van Gerwen R.J.M. 1998. Dutch Regulations for Reduction of Refrigerant Emissions: Experiences 

with a Unique Approach over the Period 1993-1998, ASERCOM Symposium, IKK, Nuremberg, 

October 1998. 

/VRO97/ Actie ‘Grote Koelinstallaties II’, Ministerie van Volkshuisvesting Ruimtelijke Ordening en 

Millieubeheer, Werkdocument 1997/345, November 1997. 
192 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Annex 1 – Authors, Co-authors and Contributors to the 2010 RTOC Report 

Dr. Radhey S. AGARWAL 

Professor, 

Mechanical Engineering Department, 

IIT Delhi, 

Senior Advisor and Co-ordinator 

Sector Phase out Plan Unit (SPPU) 

Ozone Cell, Core-4B, 2nd Floor 

India Habitat Centre, Lodhi Road 

New Delhi- 110 003 

India 

Mobile : +91 981 136 1865 

Email: rsarwal@mech.iitd.ac.in, rsagarwal@sppuindia.org 

Mr. Julius BANKS 

US EPA 

1200 Pennsylvania Avenue, NW 

Mail Code: 6205J 

Washington DC 20460 

USA 

e-mail: banks.julius@epa.gov 

Mr. James M. CALM, P.E. 

Engineering Consultant 

10887 Woodleaf Lane 

Great Falls, VA 22066-3003 

USA 

Tel: +1 703 636 9500 

E-mail: jmc@jamesmcalm.com 

Dr. Radim ČERMÁK 

Ingersoll Rand, IR Engineering and Technology 

Center Prague 

Florianova 2460 

253 01 Hostivice 

Czech Republic 

Tel.: +420 257 109 597 

Fax: +420 251 562 187 

E-mail: radim_cermak@eu.irco.com 

Prof. Guangming CHEN 

Institute of Refrigeration and Cryogenics 

Zhejiang University 

Hangzhou 310027, Zhejiang 

P.R. China 

Tel.: +86 571 8795 1680 

Email: gmchen@zju.edu.cn 

Dr. Denis CLODIC 

Emeritus Research Director 

President of innov. company ERIE 

CEP Mines-ParisTech 

5, Rue Léon Blum 

91120 Palaiseau 

France 

Tel.: + 33 1 69 19 45 02 

E-mail : denis.clodic@mines-ParisTech.fr 

Dr. Daniel COLBOURNE 

PO Box 4745 

Stratford-upon-Avon 

CV37 7DF 

United Kingdom 

Tel: +44 1789 268 285 

E-mail: d.colbourne@re-phridge.co.uk 

Mr. James G. CRAWFORD

(until his retirement) 

Trane Residential Systems 

The Trane Company / Ingersoll Rand 

6200 Troup Highway 

Tyler, TX 95707 

USA 

Tel.: +1 903 509-7273 

Email: jaygeesea@gmail.com 

Dr. Sukumar DEVOTTA 

T2/301 Skycity 

Vanagaram Ambattur Road 

Vanagaram 

Chennai 600095 

India 

Tel.: +91 44 2653 0830 

Email: sdevotta@gmail.com 

Mr. Martin DIERYCKX 

Daikin Europe 

Zandvoordestraat 300 

Oostende 8400 

Belgium 

Tel: +32 59 55 86 14 

e-mail: dieryckx.m@daikineurope.com 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 193

Mr. Dennis DORMAN 

Director 

Compressor Technology and Development 

The Trane Company 

Ingersoll Rand 

3600 Pammel Creek Road 

La Crosse, WI 54601 

USA 

Tel.: +1- 608 787 2018 

Email: ddorman@trane.com 

Mr. Kenneth E. HICKMAN 

Building Efficiency Group 

Johnson Controls 

631 S. Richland Ave. 

York, PA 17403 

USA 

Tel.: 1- 717 771 7459 

Email: kenneth.e.hickman@jci.com 

Mr. William R. HILL 

Technical Specialist, Consultant 

MACRAE, LLC 

809 Bridge Park Dr. 

Troy, MI 48098 

USA 

E-mail: Hillmich50@aol.com 

Mr. Martien JANSSEN 

Re/genT BV 

Lagedijk 22 

5705BZ Helmond 

The Netherlands 

Tel.: +31 492 476365 

E-mail: martien.janssen@re-gent.nl 

Web: www.re-gent.nl 

Mr. Makoto KAIBARA 

Panasonic Corporation 

2-3-1-1 Noji-higashi 

Kusatsu Shiga 

525-8520 Japan 

Tel.: +81-77-561-3101 

E-mail: kaibara.mak@jp.panasonic.com 

Prof. Dr. Michael KAUFFELD 

Institute of Refrigeration, 

Air Conditioning and Environmental Engineering 

Karlsruhe University of Applied Sciences 

Moltkestrasse 30 

76133 Karlsruhe 

Germany 

Tel.: +49 721 925 1843 

Fax: +49 721 925 1915 

Email: michael.kauffeld@hs-karlsruhe.de 

Mr. Fred J. KELLER, PE 

FK Consulting 

1095 Observatory Road 

Martinsville, IN 46151 

USA 

Tel.: +1 317 834 9097 

Email: fredjkeller@gmail.com 

Prof. Dr.-Ing. Jürgen KŐHLER 

Institut für Thermodynamik (IfT) 

Institute of Technology 

University of Braunschweig 

Hans-Sommer-Str. 5 

38106 Braunschweig 

Germany 

Tel.: +49 531 391 2625 

Website: www.ift.tu-bs.de 

E-mail: juergen.koehler@tu-bs.de 

Dipl. Ing. Holger KŐNIG 

CTO - UHTC 

United Heat Transfer 

Technology Center / a-heat AG 

Kemptener Strasse 99 

88131 Lindau 

Germany 

Tel.: +49 8382 30446-55 

Mobile: +49 175 520 4942 

E-mail: holger.koenig@uhtc.com 

Dr. Lambert KUIJPERS (co-chair RTOC) 

Eindhoven Center for Sustainability ECfS 

Connector 1.15b 

Het Eeuwsel 6, PO Box 513 

Technical University 

5600MB Eindhoven 

The Netherlands 

Tel.: +31 40 247 44 63 

E-mail: lambermp@planet.nl 

Mr. Edward J. McINERNEY 

Retired Chief Engineer 

General Electric 

Consumer & Industrial 

8012 Kendrick Crossing Lane 

Louisville, KY 40291 

USA 

Tel.: +1 502 718 8653 

E-mail: ejmcinerney@aol.com 
194 2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 

Prof. Dr. Ing. Petter NEKSÅ 

SINTEF Energy Research 

Energy Processes 

P.O.Box 4761 Sluppen 

7465 Trondheim 

Norway 

Mobile: +47 92 60 65 19 

E-mail: Petter.Neksa@sintef.no 

Mr. Horace NELSON 

24 Arnold Road 

Kingston 4 

Jamaica, W.I. 

Tel.: +1 876 328 6167 

E-mail : horacen@msn.com 

Dr. Roger NORDMAN 

IEA Heat Pump Centre 

SP Technical Research Institute of Sweden 

50115 Boras 

Sweden 

Tel.: +46 10 516 5544 

E-mail: roger.nordman@sp.se 

Mr. Alexander Cohr PACHAI 

Johnson Controls Denmark 

Christian D.X's Vej 201 

8270 Hoejbjerg 

Denmark 

Tel.: office +45 87 36 70 00 

Mob.: +45 29 22 71 59 

E-mail.: alexander.c.pachai@jci.com 

Dr. Andy PEARSON 

Star Refrigeration Ltd 

Glasgow 

G46 8JW 

United Kingdom 

Tel.: +44 141 638 7916 

Email: apearson@star-ref.co.uk 

Mr. Per Henrik PEDERSEN 

Danish Technological Institute 

Center for Refrigeration and 

Heat Pump Technology 

2630 Taastrup 

Denmark 

Tel.: +45 72 20 25 13 

E-mail: prp@dti.dk 

Prof. Dr. Roberto de Aguiar PEIXOTO (cochair RTOC) 

Maua Institute of Technology - IMT 

Department of Mechanical Eng. 

Praça Mauá 01 

Sao Caetano do Sul 

Sao Paulo - 09580-900 

Brazil 

Tel.: 55-11- 4239 3021 

e-mail: robertopeixoto@maua.br 

Dr. Sulkhan SULADZE 

Representative Georgia RAC Association 

30 Bldg.17 

0165 Tbilisi 

Georgia 

Mobile: +995 99 231 832 

E-mail: gra@post.ge 

Mr. Paulo VODIANITSKAIA 

HAPI Consultancy 

Rua João Colin, 1285 s.3 

89204-001 Joinville SC 

Brazil 

Tel.: +55 47 34 22 15 02 

paulo@hapiconsult.com.br 

Co-authors (non RTOC) 

Mr. Glenn C. HOURAHAN, P.E. (chapter 2)

Senior Vice President 

Air Conditioning Contractors of America (ACCA) 

2800 Shirlington Road, Suite 300 

Arlington, VA 22206 

USA 

Tel.: +1 703 824 8865 

E-mail: glenn.hourahan@acca.org, 

glenn@hourahan.com 

Contributors (non RTOC) 

Mr. Gerald CAVALIER (chapter 6) 

Cemafroid 

Parc de Tourvoie, BP 134 

92185 Antony cedex 

France 

Phone: +33 1 40 96 65 06 

Fax: +33 1 40 96 65 05 

E-mail: gerald.cavalier@cemafroid.fr 
2010 TOC Refrigeration, A/C and Heat Pumps Assessment Report 195

Dr. Mark O. McLINDEN (chapter 2) 

Chemical Engineer 

Physical and Chemical Properties Division 

National Institute of Standards and Technology 

(NIST) 

U.S. Department of Commerce 

325 Broadway, Mail Stop 838.07 

Boulder, CO 80303-3328 

USA 

Tel.: +1 303 497 3580 

E-mail: mark.mclinden@nist.gov 

Dr.-Ing. Yves WILD (chapter 6) 

Dr.-Ing. Yves Wild Ingenieurbuero GmbH 

Elbchaussee 1 

228765 Hamburg 

Germany 

Phone: +49 40 390 70 65 

Fax: 49 40 390 24 75 

E-mail: YWild@DrWild.de 

Prof. Dr. Ruhe XIE (chapter 6) 

Research Center for Logistics and Transportation 

Guangzhou University 

230 Waihuanxilu 

Guangzhou Higher Education Mega Center, 

510006 

P. R. China 

Tel.: +86 20 39366819 

Fax: +86 20 39366819 

E-mail: ruhe_xie@yahoo.com; 

rhxie@gazhu.edu.cn 

 Page 1

Excerpt of the Final Report on Global inventories of the worldwide fleets of refrigerating and air-conditioning equipment in 

order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

Annex 2: - Excerpt of the Final Report on Global inventories of the 

worldwide fleets of refrigerating and air-conditioning equipment in order to 

determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147 – December 2009 

Table of Contents 

1. GLOBAL RESULTS: REFRIGERANT DEMANDS, BANKS, AND EMISSIONS..................3 

1.1 GLOBAL DEMAND OF REFRIGERANTS IN YEAR 2006 ........................................................................3 

1.1.1 Global refrigerant demand by refrigerant types....................................................................3 

1.1.2 Refrigerant demand by application sector and by country....................................................5 

1.2 REFRIGERANT BANKS, BY APPLICATION SECTOR AND BY COUNTRY ................................................6 

1.3 REFRIGERANT EMISSIONS, BY APPLICATION SECTOR AND BY COUNTRY...........................................8 

1.4 REFRIGERANT CO2 EQUIVALENT EMISSIONS, BY APPLICATION SECTOR AND BY COUNTRY............10 

1.5 REFRIGERANT RECOVERY..............................................................................................................12 

1.6 DATA QUALITY AND DATA CONSISTENCY......................................................................................12 

2. METHOD OF CALCULATION, DATA AND DATABASES .......................................................17 

2.1 REFRIGERANT INVENTORY METHODS AND EMISSIONS CALCULATION FOR THE REFRIGERATION 

INDUSTRY ......................................................................................................................................17 

2.2 REFRIGERANTS AND REGULATIONS ...............................................................................................26 

2.3 REFRIGERANT GWPS FROM THE IPCC SECOND AND THE THIRD ASSESSMENT REPORTS..............28 

2.4 CONSISTENCY AND IMPROVEMENT OF DATA QUALITY...................................................................30 

REFERENCES ..............................................................................................................................................33 

APPENDIX 1................................................................................................................................................34 

 Page 3

Excerpt of the Final Report on Global inventories of the worldwide fleets of refrigerating and air-conditioning equipment in 

order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

1. Global results: refrigerant demands, banks, and emissions 

1.1 Global demand of refrigerants in year 2006 

The quality control of refrigerant bank and emissions is made by comparing the annual refrigerant 

demand calculated by RIEP and the annual refrigerant sales declared by manufacturers (AFEAS). 

This comparison is made refrigerant by refrigerant and is presented in Section 2.6. 

Note: the RIEP method derives, application by application, the refrigerant needs, i.e. the refrigerants charged in 

new equipment and the refrigerants charged for re-filling existing equipment. These refrigerant needs are called 

demand. 

Once the refrigerant demand has been calculated, it is cross-checked with refrigerant sales data as 

declared by refrigerant manufacturers and distributors. In many countries the refrigerant quantities 

sold are monitored; the refrigerant distributors and manufacturers publish their annual sales of CFCs, 

HCFCs, and sometimes HFC refrigerants. At the global level, AFEAS (Alternative Fluorocarbons 

Environmental Acceptability Study) publishes every year the quantities of refrigerants (by type) sold 

by the chemical manufacturers in developed countries. Those data have been used in the past to 

forecast global emissions of CFCs, HCFCs, and HFCs. 

It has to be underlined once again that 2009 is the last year of published data by AFEAS and so, from 

now on, no public data will be available for global markets of refrigerants detailed by refrigerant 

types. 

1.1.1 Global refrigerant demand by refrigerant types 

The calculation-module linked with the RIEP database allows merging refrigerant quantities by type 

as well as by application; data are presented for year 2006 in Table 2-1. 

This report presents one major change compared to the 2003 report, because of a previous 

overestimate of Chinese commercial refrigeration based on the references that were used (marketing 

reports). The consequence is that the CFC-12 demand is reduced by a factor 2 in 2006 compared to 

that calculated in the 2003 report. 
 Page 4

Excerpt of the Final Report on Global inventories of the worldwide fleets of refrigerating and air-conditioning equipment in 

order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

Table and Figure 1-1 - Global refrigerants demand from 1990 to 2006 (in tonnes) 

Refrigerant demand (t) in 2006 

R-11 6 331

CFC R-12 20 328

R-502 5 579

 

R-22 376 992

R-408A 3 443

R-401A 772

HCFC 

R-123 6 295

 

R-134a 135 569

R-404A 28 279

R-407C 24 607

R-410A 28 922

R-507 3 986

HFC 

R-413A 143

 

R-717 26 194 Others R-600a 2 869

 

Total All 670 309

Total Demand

0

100 000

200 000

300 000

400 000

500 000

600 000

700 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

tonnes

CFC HCFC HFC Others

Table 1-1 and Figure 1-1 summarise the essential developments from 1990 to 2006. The total 

refrigerant demand for all refrigerant types has increased from 345,000 tonnes in 1990 to nearly 

670,000 tonnes in 2006, which represents an increase of nearly 100%. This emphasises the impact of 

the economic growth of fast developing countries on the total, with a special mention to China. 

Globally the annual CFC refrigerant demand has decreased from 150,000 tonnes in 1990 to 32,000 

tonnes in 2006. The 2006 CFC demand represents about 5% of the total refrigerant demand. 

The annual HCFC demand has increased from 174,000 to 387,000 tonnes in 2006 (around 58% of the 

total demand) and the HFC demand that was negligible in 1990 has raised to about 221,000 tonnes in 

2006 (33% of the total demand). 

The annual ammonia demand has increased from 22,000 to 26,000 tonnes in 2006, and the HC 

demand, which was nil in 1990, is in the range of 2,800 tonnes in the year 2006. 
 Page 5

Excerpt of the Final Report on Global inventories of the worldwide fleets of refrigerating and air-conditioning equipment in 

order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

1.1.2 Refrigerant demand by application sector and by country 

Figures 1-2 and 1-3 present the refrigerant demands, including HCs and ammonia split by application 

and for the main countries or country groups. 

Demand repartition in 2006

Air to air AC

46%

Chillers

7%

Mobile AC

17%

Domestic

2%

Commercial

18%

Transport

1%

Industry

9%

Total refrigerant demand

0

100 000

200 000

300 000

400 000

500 000

600 000

700 000

199019921994199619982000200220042006

year

tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-2 – Refrigerant demand split by 

application. 

Figure 1-3 - Refrigerant demand split by country and 

country groups. 

Figures 1-4 and 1-5 present HFC demands split by application and by countries. 

HFC demand repartition in 2006

Industry

2%

Transport

2%

Commercial

14%

Domestic

6%

Mobile AC

46%

Chillers

8%

Air to air AC

22%

HFC demand

0

50 000

100 000

150 000

200 000

250 000

199019921994199619982000200220042006

year

tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-4 – HFC demand split by application. Figure 1-5 - HFC demand split by country and country 

groups. 

Figure 1.2 indicates that when all refrigerants are accounted for, the dominant sectors are commercial 

refrigeration and stationary air conditioning. For HFC demand, the dominant sector is MAC with 46 

% of the HFC demand. 

The refrigerant demand in the U.S. is still the dominant one even if the Chinese growth is the main 

driver of the total refrigerant demand. 

EU 25 needs for HFCs are around 40,000 t in 2003. In the U.S., because of the R-134a demand for 

the MAC sector, the needs are higher: 69,000 tonnes. 
 Page 6

Excerpt of the Final Report on Global inventories of the worldwide fleets of refrigerating and air-conditioning equipment in 

order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

1.2 Refrigerant banks, by application sector and by country 

The calculation of refrigerant banks requires the determination of all installed bases and fleets of 

equipment for their complete lifetime. Banks of refrigerants vary substantially in sizes and in 

refrigerant types depending on the application sector and the country. 

In 2006, the sum of all banks of all refrigerant types (see Figure 1-2) is calculated at 

2,815,000 tonnes. The global bank is roughly equal to 4.5 times the annual demand. The refrigerant 

banks and the annual refrigerant demands follow the same trends: 

 the size of the CFC bank is decreasing but, it still represents around 230,000 tonnes, which is 

about 8% of the total refrigerant bank in 2006 

 HCFCs represent 1,645,000 tonnes, which equals about 58% of the total bank 

 HFCs represent slightly less than 821,000 tonnes, which is around 29% of the total bank 

 whereas the remaining 4% of the bank consists of ammonia and HCs. 

Table 1-2 – Global refrigerant banks (t) 

Refrigerant bank (t) in 2006 

R-11 36 611

CFC R-12 173 895

R-502 17 313 

R-22 1 585 777

R-408A 10 592

R-401A 3 794

HCFC 

R-123 45 923 

R-134a 576 793

R-404A 69 354

R-407C 71 498

R-410A 93 602

R-507 8 142

HFC 

R-413A 1 979 

R-717 109 793 Others 

R-600a 10 325

TOTAL ALL 2 815 391

Bank

0

500 000

1 000 000

1 500 000

2 000 000

2 500 000

3 000 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

tonnes

CFC HCFC HFC Autres

The total refrigerant bank increased by 120% for the period from 1990 to 2006. 

Figures 1-6 and 1-7 present the refrigerant banks, including HCs and ammonia, split by application 

and for the main countries or country groups. 

Comparing Figure 1-6, which represents the global refrigerant bank by sector and Figure 1-8, which 

represents the HFC bank also by sector, it is obvious that the very different schedule of refrigerant 

changes per application leads to strong differences in the domination of one sector over the others. 

The emphasis made on mobile air-conditioning (MAC) systems for example is related to the rapid 

phase out of CFC-12 in this sector as of 1992, which consequently leads to a significant market share 

of MAC for HFCs. In fact, taking into account all refrigerants, the dominant sectors are stationary air 

conditioning and then commercial refrigeration. Those two sectors represent about 70% of the total 

use of refrigerants. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

Bank repartition in 2006

Industry

9%

Transport

1%

Commercial

12%

Domestic

Mobile AC 6%

15%

Chillers

9%

Air to air AC

48%

Total refrigerant bank

0

500 000

1 000 000

1 500 000

2 000 000

2 500 000

3 000 000

199019921994199619982000200220042006

year

tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-6 – Refrigerant bank in 2006 split by sector Figure 1-7 - Refrigerant bank - split by country. 

Figures 1-8 and 1-9 present HFC demands split by application and countries. 

HFC bank repartition in 2006

Air to air AC

19%

Chillers

9%

Mobile AC

47%

Domestic

11%

Commercial

9%

Transport

1%

Industry

4%

HFC bank

0

100 000

200 000

300 000

400 000

500 000

600 000

700 000

800 000

900 000

199019921994199619982000200220042006

year

tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-8 – HFC bank in 2006, split by sector. Figure 1-9 - HFC bank - split by country. 

57% of the total amount of refrigerants is banked in stationary air-conditioning equipment including 

chillers (9%) (see Figure 1-6). This confirms the trends observed on the annual refrigerant demand. 

Due to the rapid change from CFCs to HFCs, MAC systems (which contain only 15% of the total 

refrigerant bank) represent 47% of the total HFC refrigerant bank (see Figures 1-8 and 1-9). This 

important observation indicates the main future trends when the HCFC phase-out has to be 

accomplished. The HCFC bank is currently the largest bank and 78% (chillers included) of it is 

contained in stationary air-conditioning systems. 
 Page 8

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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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1.3 Refrigerant emissions, by application sector and by country 

Based on the bottom-up approach, taking into account all refrigerant types in all refrigerating and airconditioning systems, it is possible to derive the refrigerant emissions for all refrigerant types for the 

period from 1990 to 2000. 

Table 1-3 – Refrigerant emissions of all refrigerant types (tonnes) 

Refrigerant emissions in 2006 (t) 

R-11 6 958

R-12 35 195

CFC 

R-502 5 430 

R-22 233 686

R-408A 3 172

R-401A 958

HCFC 

R-123 3 983 

R-134a 82 825

R-404A 14 663

R-407C 7 074

R-410A 7 918

R-507 2 271

HFC 

R-413A 616 

Others R-717 19 562

R-600a 231

TOTAL All 424 542

Total emissions

0

50 000

100 000

150 000

200 000

250 000

300 000

350 000

400 000

450 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

tonnes

CFC HCFC HFC Others

Table 1-3 presents the development of emissions of all refrigerant types from 250,000 tonnes in 1990 

to 425,000 tonnes in 2006: 

 CFC emissions reach a maximum value in 1995 at 120,000 tonnes, and decrease to 47,000 in 2006 

due to their phase out, 

 HCFC emissions increase from 156,000 tonnes to 242,000 tonnes, and 

 HFC emissions increase from zero to around 115,000 tonnes. 

Yet, the sum of the CFC and HCFC emissions equals two third (68%) of all refrigerant emissions. 

Note: the management of refrigerant containers that are used every year both for charging new 

equipment and for servicing of the installed base implies the release to the atmosphere of de minimis 

quantities; the vapour heel that represents about 3% of the refrigerant charge, and often the liquid heel 

representing between 5 and 8%. For those inventories, the refrigerant heels are considered of 10% of 

the annual sales. Those emissions are not taken into account in the refrigerant emission figures 

related to refrigeration and air-conditioning equipment. 

Table 1-4 Emissions due to large containers heels (tonnes) 

2006 Domestic Commercial Transport Industry 

Air-to-Air 

AC Chillers 

Mobile 

AC TOTAL 

CFC 129 817 21 484 1 784 568 2 803 

HCFC - 6 766 213 2 206 22 384 1 728 398 33 696 

HFC 1 065 2 653 379 409 4 324 1 637 8 794 19 261 

Others 249 71 - 2 184 - 29 - 2 534 

Total 1 444 10 306 613 5 283 26 709 4 179 9 760 58 294 

Figures 1-10 and 1-11 present the refrigerant emissions, including HCs and ammonia, split by 

application and for the main countries or country groups. 
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Emissions repartition in 2006

Industry

11%

Transport

1%

Commercial

20%

Domestic

2%

Mobile AC

21%

Chillers

7%

Air to air AC

38%

Total refrigerant emissions

0

50 000

100 000

150 000

200 000

250 000

300 000

350 000

400 000

450 000

199019921994199619982000200220042006

year

tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-10 – Refrigerant emissions in 2006, split 

by sector. 

Figure 1-11 – Refrigerant emissions - split by country. 

Figures 1-12 and 1-13 present HFC emissions split by application and for the main countries or 

country groups. 

HFC emissions repartition in 2006

Air to air AC

13%

Chillers

6%

Mobile AC

61%

Domestic

2% Commercial

14%

Transport

2%

Industry

2%

HFC emissions

0

20 000

40 000

60 000

80 000

100 000

120 000

140 000

199019921994199619982000200220042006

year

tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-12 – HFC emissions in 2006, split by 

sector. 

Figure 1-13 – HFC emissions - split by country. 

Taking into account all refrigerant emissions (independently of the refrigerant type), 38% come from 

air-conditioning systems excluding chillers, 20% of emissions come from commercial refrigeration, 

and 21% from MAC systems. However, when only looking at HFC emissions, the MAC sector 

represents 61% of HFC emissions. This fact is related to the rapid shift from CFC-12 to HFC-134a, 

and to the relatively high emission factor, taking into account losses at servicing that apply to MAC 

equipment. 

Commercial refrigeration is also a significant source of emissions characterised by more than 20% of 

the total refrigerant emissions. Emission rates are three times higher in commercial refrigeration than 

they are in stationary AC. 

Domestic refrigeration, which actually is the sector with the largest number of equipment, is not a 

significant contributor to refrigerant emissions due to the small refrigerant charges and the low level of 

emissions. 

Transportation, even though characterised by a very high emission factor, is a small global contributor 

due to the relatively small number of equipment. 
 Page 10

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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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1.4 Refrigerant CO2 equivalent emissions, by application sector and by country 

The CO2 equivalent emission calculations are based on GWP values published in the Second 

Assessment Report of the IPCC. 

Table 1-5 Refrigerant CO2 equivalent emissions of all refrigerant types (tonnes) 

CO2 equiv. emissions (t) 

2nd Assessment Report 

R-11 26 440 153

R-12 285 086 629

CFC 

R-502 29 834 731 

R-22 350 532 642

R-408A 8 402 783

R-401A 932 246

HCFC 

R-123 358 515 

R-134a 107 673 924

R-404A 47 802 130

R-407C 10 794 708

R-410A 13 699 040

R-507 7 495 122

HFC 

R-413A 1 170 362

Others R-717 0

R-600a 4 617 

TOTAL All 890 227 602

CO2 Eq. Emissions

0

200

400

600

800

1 000

1 200

1990

1992

1994

1996

1998

2000

2002

2004

2006

.10e6 tonnes

CFC HCFC HFC Others

In 2006, the main contributor to global warming is HCFC-22 (39%). CFC-12 represents still 32% of 

the total contribution of all refrigerants to global warming in the year 2003, whereas the emissions of 

CFC-12 are only 8% of the total refrigerant emissions in 2006. 

HFCs, accounting for 27% of the total refrigerant emissions, contribute to only 21% of the CO2

equivalent emissions of refrigerants in the year 2006 because of the relatively low GWP of 

HFC-134a. 

Figures 1-14 and 1-15 present CO2 equivalent emissions for all refrigerants split by application and for 

the main countries or country groups. 

CO2 eq. emissions repartition in 2006

Air to air AC

27%

Chillers

8%

Mobile AC

23%

Domestic

8%

Commercial

25%

Transport

1%

Industry

8%

Total refrigerant CO2 eq. emissions

0

200

400

600

800

1 000

1 200

1 400

199019921994199619982000200220042006

year

(x1e6) tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-14 Refrigerant CO2 equiv. emissions in 

2006, split by sector. 

Figure 1-15 Refrigerant CO2 equiv. Emissions - split by 

country. 
 Page 11

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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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Figures 1-16 and 1-17 present CO2 equivalent emissions for HFC refrigerants only, split by 

application and for the main countries or country groups. 

HFC CO2 eq. emissions repartition in 2006

Industry

3%

Transport

2%

Commercial

27%

Domestic

1%

Mobile AC

50%

Chillers

5%

Air to air AC

12%

HFC CO2 eq. emissions

0

20

40

60

80

100

120

140

160

180

200

199019921994199619982000200220042006

year

(x1e6) tonnes

West and Central

Asia

South and East

Asia

Other Europe

Oceania

Latin America and

The Carribean 

EU 27

Africa

USA

Japan

India

China

Canada

Brazil

Figure 1-16 – HFC refrigerants, CO2 equiv. 

emissions in 2006, split by sector. 

Figure 1-17 HFC refrigerants, CO2 equiv. emissions - split 

by country. 

27% of the total CO2 equivalent emissions come from commercial refrigeration equipment, taking into 

account all types of refrigerants. 

For low temperature applications in commercial refrigeration, the (future) replacement of 

HCFC-22 by R-404A implies that CO2 equivalent emissions will significantly increase in this sector. 

This is due to the high GWP of R-404A (2.2 times higher than the GWP of HCFC-22). 
 Page 12

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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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1.5 Refrigerant recovery 

Table 1-6 Recovered refrigerants (tonnes) 

Refrigerant recovery (t) 

R-11 851

R-12 1 040

CFC 

R-502 146 

R-22 25 139

R-408A 712

R-401A 219

HCFC 

R-123 657 

R-134a 2 704

R-404A 526

R-407C 0

R-410A 0

HFC 

R-507 0 

Others R-717 1 625

R-600a 0

Total All 33,619

Recovery

0

5 000

10 000

15 000

20 000

25 000

30 000

35 000

40 000

199019921994199619982000200220042006

Metric tonnes

CFC HCFC HFC Others

All quantities of recovered refrigerants calculated are directly linked to the assumptions made on an 

application-by-application basis and for country groups. Very few data are available on the quantity 

that is effectively recovered. Moreover, and in particular for CFC-12, the recovered refrigerant can be 

directly re-used in other equipment without being transferred back to the refrigerant reclaim sector. A 

high level of uncertainty exists here; if real circumstances are different from the assumptions made for 

calculations, part of the quantity assumed to be recovered could well be emitted. 

1.6 Data quality and data consistency 

In this report we have taken two complementary approaches, the first one assesses the quality of 

activity data and emissions factors, the second compare the consistency of refrigerant demand as 

derived for each type of refrigerant and for all application by RIEP compared to the refrigerant sales as 

declared at the global level by AFEAS. 

1.6.1 Uncertainties 

Depending on the application sector, uncertainties are different either because activity data include 

different uncertainties or because emission factors may vary significantly from one country to the 

other. 

We have taken a simple approach that gives a quality index expressed in percentages. For activity 

data: the market, the refrigerant charge, and the equipment lifetime are the main elements that define 

the data quality. For emission factors: fugitive emissions and recovery efficiency at end of life are the 

two key parameters. 

Uncertainties on input parameters are based on expert judgements of the different sectors. These 

values are given in Table 1-7. 
 Page 13

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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

Table 1-7 Uncertainties on input parameters 

Uncertainties on input MAC SAC IND TRA COM DOM 

Equipment market (a) 2.50% 2.50% 10% 12.50% 7.50% 2.50% 

Equipment lifetime (b) 7.50% 2.50% 7.50% 2.50% 7.50% 12.50% 

Equipment average charge (c) 2.50% 12.50% 10% 7.50% 7.50% 2.50% 

Emission rate (d) 10.00% 7.50% 10% 7.50% 10% 12.50% 

Recovery efficiency (e) 10.00% 7.50% 12.50% 7.50% 12.50% 2.50% 

The calculation of the lower and upper thresholds for uncertainties is based on simplified equations 

presented in Table 1-8. It assumes that uncertainties do not change throughout the years. 

Table 1-8 Calculation of lower and upper thresholds for banks and emissions 

Results Minimum threshold Maximum threshold 

Bank 1- (a + b + c) 1+ (a + b + c) 

EOL 1 –( a + c + e) 1 +( a + c + e) 

Fugitive 1- (a + b + c + d) 1+ (a + b + c + d) 

Total emissions (Minimum EOL +Fug)/(EOL +Fug) (Maximum EOL +Fug)/(EOL +Fug) 

Based on those thresholds it is possible to evaluate the uncertainties on banks (activity data) and 

emissions. 

Table 1-9 Uncertainties on results 

 BANKS EMISSIONS 

MAC 12.5% 21.2% 

SAC 17.5% 24.4% 

IND 27.5% 37.1% 

TRA 22.5% 29.7% 

COM 22.5% 32.0% 

DOM 17.5% 12.8% 

GLOBAL 18.2% 26.6% 

1.6.2 Comparison between refrigerant demands (RIEP calculations) and refrigerant 

markets (declared by AFEAS) 

Annual refrigerant sales have been published by AFEAS since 1990. RIEP allows the calculation of 

the annual demand of refrigerants including the refrigerant charged into new equipment and 

refrigerants sold for servicing. 

AFEAS publishes data only when the cumulative sales are larger than 5,000 tonnes, and therefore data 

are not available for some components of new HFC blends, such as HFC-125, and HFC-32. 

Consumptions of all non-Article 5 countries are traced, and also of some Article 5 countries: 

Argentina, Brazil, Mexico, and Venezuela. 

The comparison of AFEAS data (declared sales) and RIEP evaluation of the refrigerant demand allows 

crosschecking the consistency of the calculation method at the global level. 
 Page 14

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♦ CFC demand 

Before 1995 the demand is lower than the sales. 

After the phase-out date of the CFC production, the 

sales declared by AFEAS decrease rapidly to nearly 

a zero value in 2000, but the demand still exists 

during this period. This difference can be explained 

by a stock-piling effect (end-users buy refrigerant 

when allowed in order to maintain the CFC-11 

chillers after the phase-out date). 

The cumulative difference between AFEAS 

(116,000 t) data and refrigerant CFC-11 need as 

derived by RIEP (203,000 t) indicates that the CFC11 has been produced by manufacturers of A5 

countries not reporting to AFEAS and the 

cumulative demand. 

CFC-11

0

5 000

10 000

15 000

20 000

25 000

1990

1992

1994

19961998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-18 – Comparison of CFC-11 demand between 

AFEAS sales and RIEP calculations 

When comparing the sales as declared by 

AFEAS and the demand as calculated by 

RIEP, the stock-piling effect from 1990 to 

1995 seems obvious. When making the sum of 

the CFC-12 sold from 1990 to 2006 and the 

demand as derived also for the same period, 

RIEP leads to 1,236,000 t and AFEAS leads to 

1,069,000 t (1990 to 2003), leading to a 

negligible difference on those 13 years. This 

seems to confirm that sales and usages are 

disconnected when regulation forbids the sales 

of refrigerant and tolerates the operation of 

refrigerating systems after the end of 

refrigerant commercialisation.

CFC-12

0

20 000

40 000

60 000

80 000

100 000

120 000

140 000

160 000

180 000

200 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-19 Comparison of CFC-12 demand between 

AFEAS sales and RIEP.

CFC-115 is one of the two components of R502. 

The cumulated demand between 1990 and 

2006 is 82,000 t, compared to the cumulated 

demand of 75,000 t. 

Considering a stock-piling effect beginning in 

1989, the difference of cumulated demand and 

demand is very low. 

R-115

0

2 000

4 000

6 000

8 000

10 000

12 000

14 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-20 Comparison of CFC-115 demand between 

AFEAS data and RIEP calculations.
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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♦ HCFC demand

The comparison between the HCFC-22 

demand and the HCFC-22 sales by 

manufacturers reporting to AFEAS shows 

clearly the impact of HCFC-22 production in 

developing countries. It is certainly a reason 

why AFEAS has stopped at the end of 2009 

to make this reporting for HCFC-22. It 

appears that more of it is produced out of 

AFEAS manufacturers. 

The cumulative production as reported by 

AFEAS from 1990 to 2006 is of 3,245,000 

tonnes, and the cumulative needs calculated 

by RIEP are of 4,600,000 tonnes.

HCFC-22

0

50 000

100 000

150 000

200 000

250 000

300 000

350 000

400 000

450 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-21 –– Comparison of HCFC-22 demand 

between AFEAS data and RIEP calculations

♦ HFC demand 

The HFC-134a demand calculated by RIEP is 

very closed to the declarations of sales. 

The growth rate is similar and the cumulated 

values from 1990 to 2006 are quite the same: 

1,181,000 tonnes for the total sales (RIEP) and 

991,000 tonnes for the cumulated demand 

(AFEAS), which is still a difference of about 

15%. One of the main issues is to verify if the 

emission rates of MAC systems have been 

effectively decreasing as modelled in RIEP since 

2000.

HFC-134a

0

20 000

40 000

60 000

80 000

100 000

120 000

140 000

160 000

1990

19921994

1996

1998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-22 Comparison of HFC-134a demand 

between AFEAS data and RIEP calculations

HFC-125

0

5 000

10 000

15 000

20 000

25 000

30 000

35 000

40 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-23 Comparison of HFC-125 demand between 

AFEAS data and RIEP calculations

HFC-125 is used in refrigerant blends such as R404A, R-507, R-410A, and R-407C. 

The trend is the same between sales as reported by 

AFEAS and the demand as calculated by RIEP. It 

can be noticed that even if AFEAS data were 

missing in 2003, the RIEP derivation leads to 

similar evaluation of HFC-125 needs in 2006. 

These results confirm that the assumptions for 

refrigerant changes are good and that HFC-125 is 

manufactured only AFEAS manufacturers. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

HFC-143a

0

2 000

4 000

6 000

8 000

10 000

12 000

14 000

16 000

18 000

20 000

1990

1992

1994

1996

1998

2000

2002

2004

2006

Riep

AFEAS

Figure 1-24 Comparison of HFC-143a demand 

between AFEAS data and RIEP calculations

HFC-143a is used in refrigerant blends 

(R-404A, and R-507) for low-temperature 

applications, in commercial refrigeration, and 

mainly in Europe. 

The trend is the same between sales, as reported by 

AFEAS, and the demand as calculated by RIEP. So 

lessons from the comparison are identical to those 

drawn for HFC-125. 

♦ Total demand 

The trend as shown by RIEP indicates the dominance of HCFC-22 sales, which makes the difference 

between AFEAS data and RIEP calculations since 1998. As shown in the previous charts analysing 

sales and demand refrigerant by refrigerant, the only significant difference between AFEAS data and 

RIEP calculation is related to HCFC-22. 

Figure 1-25 – Comparison between AFEAS sale data and RIEP calculated refrigerant needs 

TOTAL

- 

100 000 

200 000 

300 000 

400 000 

500 000 

600 000 

700 000 

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008

total RIEP AFEAS
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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2. Method of calculation, data and databases 

2.1 Refrigerant Inventory methods and emissions calculation for the refrigeration 

industry 

UNFCCC collects every year from signatory countries their national inventories of greenhouse gases. 

Three methods, Tier 1, Tier 2, and Tier 3 are proposed by the IPCC guidelines to help countries 

making their inventories. The refrigeration and air-conditioning industry emissions are either 

inventoried by sales of refrigerants or by sales of all refrigeration and air-conditioning equipment. 

The six main sectors for the refrigeration and air conditioning (RAC) are: 

- Domestic refrigeration 

- Commercial refrigeration (centralised systems, condensing groups, and standalone equipment) 

- Industrial and food processes 

- Transport refrigeration 

- Stationary air conditioning 

- Mobile air conditioning. 

This section presents the methodologies proposed by the IPCC guidelines for the estimation of GHG 

emissions. The RIEP model developed by the CEP is a “bottom-up” approach based on the Tier2a 

methodology. Some improvements have been introduced in this 2006 inventory report. 

The Tier 2 IPCC method 

The 1996 IPCC Guidelines provide step-by-step instructions for establishing national greenhouse 

gases inventories: “directions for assembling, documenting, and transmitting completed national 

inventory data consistently”. 

Two calculation methods were developed for the estimation of emissions of fluorinated greenhouse 

gases and their substitutes for the refrigeration and air-conditioning sectors, the Tier 1 and Tier 2 

methods. The Tier 3 method relies on actual monitoring and measurement of emissions from point 

sources and is not used in the refrigeration since the sources are diffuse [IPC06]. 

RIEP being based on the TIER 2 and its improvements, the Tier 2 methodology needs to be presented 

per se. This method calculates the actual emissions for each individual chemical in a given year on an 

application basis. It takes into consideration that there might be a considerable delay between the time 

where the fluid is produced and charged in equipment, and the time where it is released into the 

atmosphere. 

First, it estimates the consumption of each individual chemical, at an application basis level, in order 

to establish the global volume from which emissions originate. An application might use several 

chemicals; typically in refrigeration, blends of refrigerants are used in several applications. They have 

to be inventoried component by component for UNFCCC reporting. 

This method might be implemented in two different ways: the “bottom-up” approach (application 

based) or the “top-down” approach (national consumption derived). 

In a “bottom-up” approach, one evaluates the consumption of a certain refrigerant based on the 

number of equipment in which the fluid is charged, e.g. refrigerators, stationary air-conditioning 

equipment, and so on. It requires the establishment of an inventory of the number of equipment 

charged with inventoried substances, and the knowledge of their average lifetime, their emission rates, 

recycling, disposal, and other parameters. Annual emissions are then estimated as functions of these 

parameters during the equipment lifetime. 
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A “top-down” approach estimates emissions for a given year on the basis of the national consumption 

of chemicals: it disaggregates chemical consumption data into sectors using distribution factors and 

then applies time-dependent emission factors. The access to such data might be very difficult due to 

confidentiality issues. Although in some cases producers might report to their government the 

quantity of a certain fluid sold into a specific sector, in other cases, when the chemical is sold by many 

distributors before reaching its application, it might be difficult to collect the corresponding needed 

data [IPC00]. In such cases, estimating of distribution factors is based on expert judgements. 

In the IPCC 2006 guidelines, the mass-balance and the emission-factor approaches were introduced. 

The Tier 1 method addresses the total refrigeration and air-conditioning sector; the Tier 2 method 

requires information for each type of equipment in the six application sectors defined above. 

For the mass-balance approach, emissions are calculated as follows: 

(2.1)

The limitation on the application of Equation (2.1) to MAC systems will be explored in the next 

paragraphs. 

Refrigerant emissions from refrigeration and air-conditioning systems occur at three main levels: 

emissions during the charging process, emissions from the existing bank, and emissions at the 

equipment disposal. 

The emission-factor approach adds the emissions related to the management of containers Econtainers,t to 

those cited above, and equations for this approach are provided below. 

The total emissions of a given refrigerant in year t Etotal, t are given by Equation (2.2) 

(2.2) 

Where, 

Econtainers,t Emissions related to the management of refrigerant containers 

Echarge,t Emissions occurring during the charging process of the new equipment 

Elifetime,t Emissions occurring during the equipment lifetime 

Eend-of-life,t Emissions occurring at equipment disposal 

Emissions related to the management of refrigerant containers 

Emissions at the fluid manufacturing stage occur from the feedstock materials in chemical processing 

plants. The good design and operation of the plant lead to relatively low emissions [IPC05]. These 

emissions are not counted within the methods under discussion. 

Once manufactured, fluids are loaded in large containers, or in individual cylinders. They are 

therefore delivered to product manufacturers in bulk quantities or into smaller containers. Emissions 

can occur at this level of fluid handling: splitting the bulk refrigerant from large containers into 

smaller volumes of refrigerant. Capacity heels are also considered as a main loss during the 

refrigerant handling. The “heels” consist of both the liquid and vapour inside the container, which 

cannot be extracted due to the pressure equilibrium between the vapour (the vapour heel) and the 

liquid phase remaining in the refrigerant volume (the liquid heel). 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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Emissions related to the management of containers are considered between 2 and 10% of the total 

refrigerant market [IPC06]. 

 

(2.3) 

Where, 

RMt The refrigerant market for new equipment and servicing in year t 

c The emission factor of the management of refrigerant containers expressed in percentage 

Emissions occurring when charging new equipment 

At this stage, emissions occur when the refrigerant containers are connected to or disconnected from 

the equipment being charged. These emissions are usually higher for field-assembled and fieldcharged equipment than for the factory-produced ones. For example, these emissions include those 

taking place when hoses and valves are being connected or disconnected [CLO05]. 

All systems charged in a country in a given year t, including those that are exported are taken into 

account for the calculation of Echarge,t as shown in Equation (2.4). Systems being imported are not 

considered [CLO05]. 

(2.4) 

Where, 

Mt The amount of refrigerant charged into new equipment in year t 

k The emission factor occurring during assembly expressed in percentage; it ranges between 2 and 

5%. 

Emissions occurring during the equipment lifetime 

For most applications, the largest emissions take place particularly during the in-use stage and depend 

on the application type. For example, domestic refrigerators show very low emission rates during 

their lifetime, due to their hermetically sealed technology, whereas centralised systems in the 

commercial refrigeration sector experience the highest annual emission rates, up to 30% of their initial 

charge. These emissions generally originate from leakage of fittings, joints, and seals but also from 

ruptures of pipes and from the refrigerant handling during servicing operations. These rates vary 

among applications and countries depending on the technology, operating conditions, and the 

servicing quality. These emissions are calculated as shown in Equation (2.5) and include those 

occurring during servicing. 

(2.5) 

Where, 

Bt The bank of refrigerant contained in all existing equipment in year t for all vintages 

x The emission factor of annual leakage from the bank occurring in year t, given in percentage 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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Emissions occurring at equipment disposal 

Emissions from equipment at end of life depend on country regulations affecting the recovery 

efficiency at disposal. Parameters used for the calculation of these emissions are shown in Equation 

(2.6). 

(2.6) 

Where, 

Mt-d The amount of refrigerant charged into new equipment in year t-d, reaching the end of life at age 

d 

p The remaining charge in the equipment being disposed of, expressed in percentage of the initial 

charge 

ηend-of-life,t The recovery efficiency at end of life, expressed in percentage of the remaining charge in the 

system 

At the equipment end of life, several scenarios for fluid handling exist: 

• The fluid is not recovered (ηend-of-life,t = 0), thus the remaining refrigerant quantity in the 

equipment constitutes the end of life emissions 

• The fluid is recovered. After this, it can be considered as waste, and therefore is either 

destructed or emitted or disposed of. Alternatively, the recovered fluid can be reclaimed or 

recycled. 

Choice of method for the refrigeration and air-conditioning sectors 

Refrigeration and air-conditioning sectors are disaggregated in six sub-sectors. However, due to the 

diversity of equipment that can be found within the same sector, a more disaggregated level is needed 

in order to calculate the emission factors and the activity data, such as equipment lifetime, average 

charge, and refrigerant type. For example, if we consider the commercial refrigeration sector, the 

emission factor varies widely between the different refrigerating systems that can be found within this 

sector: the emission factor for standalone equipment is in the range of 1% and, as said before, for large 

centralised systems it can reach 30%. 

The mass-balance approach (Equation 2.1) shows limitations especially when the recharge 

frequency is not on annual basis as for MAC systems: what enters for the servicing in a given year is 

not equivalent to what has been emitted. A delay of 5 to 8 years could be observed. In a mature 

market, where the average charge of the MAC system does not change and emission characteristics are 

also constant along time, this model could be applied since vehicle characteristics are identical, and the 

refrigerant stock does not change, which means that what is emitted 8 years ago is equal to what is 

emitted that year. This is not pretty much realistic due to the leak tightness improvements being 

observed on the MAC systems since the introduction of HFC-134a. Moreover, it is totally unrealistic 

when the market growth is significant as in Europe since 1995 and now in Asia. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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Figure 2-1 shows a comparison of total emissions for MAC systems, as calculated by the emissionfactor and the mass-balance approaches. 

Total emissions comparison

0

200

400

600

800

1,000

1,200

1,400

1,600

1,800

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

year

tonnes

Mass-balance approach Riep model

Figure 2-1 - Comparison of total emissions based on the mass-balance and the emission-factor approaches 

for MAC systems in France. 

The mass-balance approach underestimates the emissions coming from the MAC systems as it can be 

seen on Figure 2- The difference between both methods is mainly due to the time lag between 

emissions and servicing consumption as explained previously. 

The RIEP calculation method 

The Center for Energy and Processes (CEP) developed a global database for the refrigeration and airconditioning application, containing the required activity data and emission factors for the 

establishment of refrigerant inventories for countries and regions of the United Nations. A calculation 

model, called RIEP (Refrigerant Inventories and Emission Previsions), was developed based on a 

bottom-up approach as defined in IPCC 2000 [IPC00]. The work done by the CEP during the last 

eight years was taken into account for the update of the Tier 2 method as described in the IPCC 2006 

guidelines [CLO05], [ASH04]. The covered sub-sectors are those listed previously, defined by the 

IPCC 2006 guidelines, and the disaggregation leads to the definition of 35 sub-sectors. 

Improvements of the RIEP calculation method 

A series of improvements of the RIEP calculation method has been done by S. Saba for her thesis 

work [SAB09]. Those refinements are important in order to figure out more precisely activity data 

such as equipment lifetime and emission factors. 

Emission factors 

Equations used for the emission-factor approach of the Tier 2 method are the basis of the general 

calculation method implemented in RIEP. Still, some particularities might appear for each sub-sector 

requiring specific input parameters and therefore some modifications to the main calculation 

algorithm. The method was adapted to the sub-sectors based on the availability of the activity data 

and the emission factors. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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For example, for the commercial centralized systems, chillers, and industrial refrigeration, emission 

factors are established based on purchase invoices of refrigerants. The amount of refrigerant 

purchased includes the refrigerant used to replace the losses from leakages and the losses during the 

system servicing, and therefore both types of emissions are considered within the emission factor, 

which is then applied to the refrigerant bank. The same methodology is not possible for MAC or 

stationary air-conditioning systems. Sources of information of emission factors for this sector are 

scarce; some studies provide numbers on the initial leak flow rate (LFR) and others give numbers on 

the LFR of a fleet of vehicles from different vintages. 

The calculation method implemented in RIEP considers an overall emission factor including “regular” 

and “irregular” emissions resulting from road accidents and accidents taking places in garages. 

Regular leaks are the leaks related to joints, seals, and every location where one can find clearances 

between metallic parts with an elastomeric seal. Those regular leaks increase along the time due to 

wear and vibration, so the emission factor increases along the vehicle lifetime. Why a degradation 

factor has to be taken into account rather than an average value? Because the regular leaks are known 

from test on new systems, those values are low and do not explain the refrigerant sales dedicated to 

servicing in the Mobile-Air conditioning sector. Using an initial LFR increasing with time instead of 

an average value implies a different schedule for the maintenance operations. Taking the assumption 

of a degradation factor, a vehicle will undergo maintenance at the 6th year, then at the 9th, while 

assuming single average the vehicle will undergo maintenance every 4 years. 

In summary, for MAC systems, the emissions factor is split in two factors: 

- the “regular LFR” with an initial value given per vintage associated with a degradation factor, 

and 

- the “irregular LFR” taking into account accidents. 

A complementary algorithm is implemented for servicing taking into account emissions occurring 

during the maintenance Eservicing,t. 

Change of refrigerant by retrofit 

The RIEP model identifies retrofit operations for the sectors where they are occurring, and the related 

emissions Eretrofit,t. 

Refrigeration system retrofit consists in replacing a former refrigerant (CFC or HCFC), which use is 

no longer possible either due to regulation or due to shortage of sales by a new one adapted to the 

system and in conformity with the regulation. The operation consists in recovering the “old” 

refrigerant from the refrigeration system, evacuating the system, and recharging the system with the 

new refrigerant. For the recovery operation, recovery efficiency is defined, the complementary 

percentage being emitted. The amount of refrigerant being replaced is calculated based on the retrofit 

schedule of the remaining bank of this refrigerant; for every year a percentage of this refrigerant bank 

being replaced. 

Retirement curve instead of average lifetime 

Another modification applied to the RIEP model is the use of a retirement curve to account for the 

equipment being disposed of instead of the mean lifetime used in the previous version. The modified 

equations taking into account the retirement curve are presented now. Equations related to the mean 

lifetime are taken from Clodic [CL005] and Ashford et al. [ASH04]. 
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Hereafter, equations are given for mean lifetime and retirement curves: 

(2.7)

(2.8) 

Where, 

Bt The bank of refrigerant at year « t » expressed in kilograms 

Mv The amount of refrigerant charged into new equipment for vintage v (per application category) 

expressed in kilograms and calculated by multiplying the national sales of equipment by the average 

charge of equipment 

ml The mean lifetime of the system 

Ml The maximum lifetime of the system when using a retirement function 

r,v,t The remaining installed base of equipment of vintage v at year t expressed as a fraction of the initial 

number 

Then, it can be seen that the bank calculation requires the knowledge of the mean lifetime for Equation 

(2.7) or the establishment of a retirement curve for Equation (2.8). The national sales of equipment as 

well as its average charge should also be known. The access to this activity data might be difficult 

especially for years before the Montreal Protocol. 

For some sectors, such as the commercial refrigeration sector, emission factors are applied directly to 

the banks and Equation (2.5) is used to calculate emissions along the lifetime, taking indirectly into 

account the retirement curve for the bank calculation. 

For MAC systems, the algorithm presented in Figure 2.2 is used to calculate emissions due to 

servicing, regular, and irregular emissions. 

Emissions during lifetime are calculated as follows, according to the lifetime option: 

- mean lifetime, Equations (2.9) and (2.10) are used 

- when using a retirement curve, Equations (2.11) and (2.12) are chosen..: 

* If the system is not empty

(2.9)

* If the system is not empty

(2.10) 

* If the system is not empty

(2.11)

* If the system is not empty

(2.12) 

Where, 

Nv The number of equipment of vintage v 

LFRv The LFR value of vintage v at year t expressed in g/year 

EFirr,t The emission factor for irregular emissions at year t expressed in g/year 

rv,t The remaining installation of vintage v in year t expressed as a fraction of the initial number 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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Servicing emissions are calculated by Equations (2.13) and (2.14): 

* If the vintage requires servicing 

(2.13)

* If the vintage requires servicing

(2.14) 

Where, 

sv,t The residual charge of vintage v in year t expressed in percentage 

ηserv,t The recovery efficiency at servicing expressed as a fraction of the amount contained in the 

equipment being recharged 

The algorithm presented in Figure 2.2 describes how emissions during servicing operation are taken 

into account for MAC systems. This algorithm is applied to all vehicle vintages. The recharge is 

required when the refrigerant emitted is over a threshold corresponding to 50% of the initial charge. 

For every year j, the refrigerant loss is calculated by Equations (2.9) or (2.11). The loss is compared 

to the threshold of residual refrigerant charge, which requires the AC system maintenance due to the 

lack of cooling capacity. 

If the loss is larger than this quantity, and the MAC system did not reach its end-of-life, the system 

undergoes maintenance and the amount of refrigerant required for the servicing operation and 

emissions occurring during this operation are calculated for this year of recharge. After this 

intervention, the system is fully charged again. 

However, if the loss is lower than the threshold leading to maintenance, no maintenance occurs at this 

year of calculation, which is then incremented. Losses calculated for the following year are then 

added to those previously calculated, and the threshold for maintenance is then verified. If the 

condition for maintenance is verified, the maintenance operation takes place as described previously; 

otherwise, the year of calculation is incremented again until the MAC system reaches its end-of-life. 

As a result of this calculation algorithm, the sv,t parameter used in Equation (2.13) or (2.14) is 

calculated dynamically each year the system undergoes maintenance. The same thing applies to the 

end-of-life emissions that are calculated dynamically for this sector. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

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Figure 2.2 - Refrigerant servicing demand and emissions for MAC systems. 

Retrofit emissions Eretrofit,t are calculated using Equation (2.15) 

(2.15) 

Where, 

Mrefrigerant-out,t The refrigerant being replaced at year t 

ηend-of-life,t The recovery efficiency at end of life in year t expressed as a fraction of the 

remaining amount of refrigerant being recovered 

Total emissions during the lifetime are given by Equation (2.16): 

(2.16) 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

Emissions during servicing and retrofit given by Equation (2.17) occur during the refrigerant recovery. 

However, when the refrigerant is being re-introduced, emissions can take place. Those emissions do 

not appear in equations provided by [CLO05] or the IPCC 2006 guidelines, and can be written as 

follows: 

 (2.17) 

Where, 

RSt Refrigerant demand for servicing at year t 

RRt Refrigerant demand for retrofit at year t 

k The emission factor at the charging process expressed in percentage 

End-of-life emissions are calculated by Equation (2.6) when an average lifetime is used, whereas they 

are calculated by Equation (2.18) when using a retirement curve: 

(2.18) 

Where, 

rv,t-1 The remaining installation of vintage v at year t-1 

rv,t The remaining installation of vintage v at year t 

For MAC systems, the residual charge at end-of-life is calculated for every vintage; therefore the value 

of p in Equation (2.18) depends on the vintage and on the year of disposal. 

2.2 Refrigerants and regulations 

The use of CFCs, HCFCs or HFCs and other refrigerants is related to control schedules, which have 

been continuously adjusted since the Montreal Protocol has been ratified. For the developed countries 

(the non-Article 5 countries as defined in the Montreal Protocol), the phase-out of CFCs and HCFCs 

will be earlier than in developing countries (the Article 5 countries). Moreover, where it concerns 

non-Article 5 countries, the European Union has accepted a much tighter control schedule for phasing 

out (CFCs in the past and) HCFCs. 

The rapid phase out of CFCs in Europe and also the interdiction of use of CFCs for servicing have led 

to a significant uptake of intermediate blends (HCFC-based blends) for the retrofit of a number of 

refrigerating systems using CFCs. The retrofit allows keeping the residual value of equipment until its 

usual end of life. It is likely that the same behavior of equipment owners will be followed for the 

progressive phase out of HCFCs, which will be replaced by intermediate blends of HFCs. Based on 

these facts, RIEP includes retrofit options where the refrigerant can be changed during the equipment 

lifetime. 

♦ Non-Article 5 countries 

The CFC phase-out schedule as valid for the non-Article 5 countries is presented in Figure 2.3. Via 

the EU regulation 3093/94, CFCs were phased out one year before the phase-out defined in the 

Montreal Protocol, i.e. on 31 December 1994. 
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CFC Production and consumption (base 1986)

0%

20%

40%

60%

80%

100%

120%

198619881990199219941996199820002002200420062008201020122014

HCFCs consumption reduction (ODP eq.)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Base 1996 = 100%

HCFC base 1989 +

2.8% CFC base

1989

Figure 2.3 – CFCs phase out in non Article 5 countries. Figure 2.4 – HCFCs phase out in non Article 5 countries 

(except EU).[MOP07].

As indicated in Figure 2.4, the HCFC consumption base levels refer to the 1989 HCFC consumption 

plus 2.8% 1989 CFC consumption, ODP-weighted. On the basis of a certain ODP for HCFC-22 and 

CFCs (0.055 and 1.0 respectively), the factor of 2.8% means that if all CFCs were to be replaced by 

HCFC-22, about 55% of the CFC consumption in tonnes would be replaced by HCFC-22. 

Figure 2.3 clearly shows that, even for non-Article 5 countries, brand-new equipment can be 

manufactured, charged with HCFC-22, and sold until 31 December 2009. Typically, the U.S. and 

many developed countries continue to use HCFC-22 for air-conditioning equipment. 

As indicated in Figure 2.5, the 

EU regulation has changed the 

baseline level for the HCFC 

consumption by reducing the 

additional quantities of ODP 

weighted CFCs by nearly 30% 

(from 2.8 to 2.0%). Moreover, 

the time of the HCFC phaseout is been brought forward by 

about 7 years. 

HCFC consumption reduction 

(base 1996)

Base 1996 = 

100% HCFC (base 1989) 

+ 2 % CFC (base 1989)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

1996199820002002200420062008201020122014

ODP eq.

Figure 2.5 - European Union - (European regulation 2037/2000).
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

♦ Article 5 Countries 

The CFC consumption and production 

(see Figure 2.6) for Article 5 countries 

have a delay compared to non-Article 

5 countries of actually 14 years (1996 

compared to 2010). There is an 

additional possibility of production 

and consumption of 10% compared to 

the 1996 level for Basic Domestic 

Needs of developing countries where 

production can take place in developed 

countries. 

CFC Production and consumption (base 1986)

0%

20%

40%

60%

80%

100%

120%

198619881990199219941996199820002002200420062008201020122014

Figure 2.6 - CFC phase-out for Article 5 Countries.

For the HCFC phase-out, the Montreal Protocol schedules are slightly more complicated. Where it 

concerns the freeze in consumption, Article 5 countries have a delay of about 15 years (freeze by 

2016). Where it concerns the phase-out, it is a 10-year delay period (phase-out in 2040 versus 2030) 

for the developing countries compared to the developed ones. 

All these different constraints based on global control schedules and more stringent regional 

and national regulations imply different refrigerant choices in countries and country groups. 

The refrigerant choices need to be taken into account on an application by application basis. 

In this project, additional data, derived from country reports, have been used as well as data 

available in publications. 

2.3 Refrigerant GWPs from the IPCC Second and the Fourth Assessment Reports 

Table 2.1 lists the main refrigerant types in use: CFCs, HCFCs, HFCs, ammonia, and different blends, 

many of them being intermediate blends used for retrofit of CFC equipment. Table 2.1 has been 

updated taking into account all new blends as declared to ASHRAE 34. Among those blends, the 

most used of are R-401A, R-409A, and R-413A for the replacement of CFC-12, R-402A and B, and 

R-408A for the replacement of R-502. The use of those blends can be verified at the global level by 

the declarations of sales by AFEAS of HCFC-124 and HCFC-142b, which are specific components of 

those intermediate blends. The list is nearly exhaustive, and takes into account more than 99% of all 

refrigerant types in use. 

The GWP values, as given in the Second Assessment Report of the IPCC (SAR), are used for the 

calculations of the equivalent CO2 emissions of refrigerants as shown in Table 2.1. The latest 

scientific values of refrigerant GWPs are coming from the 4th Assessment Report of IPCC. As it can 

be observed below, they are virtually all higher than the GWP values published in the 2nd Assessment 

Report. Nevertheless, in the RIEP calculations, the SAR report values have been kept because they 

are those used for reporting HFC emissions to UNFCCC. GWPs of mixtures have been calculated 

from the separate components. 

For latest GWP values, based upon the Fourth Assessment Report as well as the 2010UNEP/WMO 

Scientific Panel Assessment Report reference is made to chapter 2 in this 2010 RTOC report, which 

contains all latest GWP values for pure substances and for mixtures and blends. 
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Table 2-1 GWP and physical data of refrigerants [TOC03, IPCC07] 

Refrigerant Physical data GWP 

GWP 

SAR 

GWP 

Number Chemical formula or blend composition – AR4 

common name 

Molecular 

mass NPB (°C) TC (°C) Pc (MPa) 1996 2007 

11 CCl3F 137.37 23.7 198.0 4.41 3 800 4750 

12 CCl2F2 120.91 -29.8 112.0 4.14 8 100 10890 

22 CHClF2 86.47 -40.8 96.1 4.99 1 500 1810 

32 CH2F2-methylene fluoride 52.02 -51.7 78.1 5.78 650 675 

115 CClF2CF3 154.47 -38.9 80.0 3.12 9 300 7370 

116 CF3CF3-perfluoroethane 138.01 -78.1 19.9 3.04 9 200 12200 

123 CHCl2CF3 152.93 27.8 183.7 3.66 90 77 

124 CHClFCF3 136.48 -12.0 122.3 3.62 470 609 

125 CHF2CF3 120.02 -48.1 66.1 3.63 2 800 3500 

134a CH2FCF3 102.03 -26.1 101.1 4.06 1 300 1430 

143a CH3CF3 84.04 -47.2 72.7 3.78 3 800 4470 

152a CH3CHF2 66.05 -24.0 113.3 4.52 140 124 

245fa CHF2CH2CF3 134.05 15.1 154.0 4.43 1030 

290 CH3CH2CH3 - propane 44.10 -42.1 96.7 4.25 

401A R-22/152a/124(53/13/34)-MP39 94.44 -32.9 107.3 4.61 973 

401B R-22/152a/124(61/11/28)-MP66 92.84 -34.5 105.6 4.68 1 062 

402A R-125/290/22(60/2/38)-HP80 101.55 -48.9 75.9 4.23 2 250 

402B R-125/290/22(38/2/60)-HP81 94.71 -47.0 82.9 4.53 1 796 

403A R-290/22/218(5/75/20) 91.99 -47.7 87.0 4.7 2530 

403B R-290/22/218(5/56/39) 103.26 -49.2 79.6 4.32 3570 

404A R-125/143a/134a(44/52/4) 97.60 -46.2 72.0 3.74 3 260 

405A R-22/152a/142b/C318(45/7/5.5/42.5) 111.91 -32.6 106.1 4.29 4480 

406A R-22/600a/142b(55/4/41) 89.86 -32.5 116.9 4.96 1560 

407A R32/125/134a(20/40/40) 90.11 -45.0 81.8 4.52 1770 

407B R32/125/134a(10/70/20) 102.94 -46.5 74.3 4.13 2290 

407C R-32/125/134a(23/25/52) 86.20 -43.6 85.8 4.63 1 526 

407D R-32/125/134a(15/15/70) 90.96 -39.2 91.2 4.47 1430 

407E R-32/125/134a(25/15/60) 83.78 -42.7 88.3 4.7 1360 

408A R-125/143a/22(7/46/47)-FX-10 87.01 -44.6 83.1 4.42 2 649 

409A R-22/124/142b(60/25/15)-FX-56 97.43 -34.4 109.3 4.69 1 288 

410A R-32/125(50/50)-Suva9100;AZ-20 72.58 -51.4 70.5 4.95 1 730 

411A R-1270/22/152a(1.5/87.5/11) 82.36 -39.5 99.1 4.95 1330 

412A R-22/218/142b(70/5/25) 92.2 -38 107.2 4.9 1850 
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Refrigerant Physical data GWP 

GWP 

SAR 

GWP 

Number Chemical formula or blend composition – AR4 

common name 

Molecular 

mass NPB (°C) TC (°C) Pc (MPa) 1996 2007 

413A R-218/134a/600a(9/88/3) 103.95 -33.4 96.6 4.07 1770 

414A R-22/124/600a/142b(51/28.5/4/16.5) 96.93 -33.0 112.7 4.68 1200 

415A R-22/152a(82/18) 81.91 -37.2 102.0 4.96 

416A R-134a/124/600(59/39.5/1.5) 111.92 -24.0 107.0 3.98 

417A R-125/134a/600(46.6/50/3.4) 106.75 -39.1 87.3 4.04 

418A R-290/22/152a(1.5/96/2.5) 84.60 -41.7 96.2 4.98 

419A R-125/134a/E170(77/19/4) 109.3 -42.6 79.3 4 

420A R-134a/142b(80.6/19.4) 101.84 -24.9 104.8 4.11 

421A R-125/134a(58/42) 111.75 -40.7 82.9 3.88 

422A R-125/134a/600a(85.1/11.5/3.4) 113.60 -46.5 71.8 3.92 

427A R-32/125/143a/134a(15/25/10/50) 90.44 -43.0 85.1 4.39 1827 

500 R-12/152a(73.8/26.2) 99.30 -33.6 102.1 4.17 6 014 

502 R-22/115(48.8/51.2) 111.63 -45.2 80.2 4.02 5 494 

503 R-23/13(40.1/59.9) 87.25 -87.8 18.4 4.27 11 700 

507A R-125/143a(50/50)-AZ-50 98.86 -46.1 70.5 3.79 3 300 

1270 CH3CH=CH2 - propylene 42.08 -47.7 92.4 4.66 

600a CH(CH3)2-CH3 - isobutane 58.12 -11.7 134.7 3.64 

717 NH3 – ammonia 17.03 -33.3 132.3 11.33 

744 CO2 44.01 -78.4 31.0 7.38 1 

NBP = normal boiling point; Tc = critical temperature; Pc = critical pressure; GWP = global warming 

potential (for 100-yr integration). 

The GWP calculation for blends is based on the GWP values of pure refrigerants, and their mass 

concentration in the blend. All values for blends are coming from the 2006 TOC Report [TOC06] 

2.4 Consistency and improvement of data quality 

The refrigerant demand calculated by RIEP for each refrigerant, including charge of new equipment 

and recharge of the installed base to compensate refrigerant emissions, is compared to refrigerant sales 

declared by refrigerant distributors. 

Equation (2.19) calculates the refrigerant demand, which is then compared to the declared numbers. 

(2.19) 

Where, 

Rt The total refrigerant demand at year t, expressed in kilograms 

RPt The total refrigerant demand for the new equipment being charged in the country, expressed in 

kilograms 

RSt The refrigerant demand for servicing at year t, expressed in kilograms 

RRt The refrigerant demand for retrofit at year t, expressed in kilograms 

c The emission factor of the management of refrigerant containers, expressed in percentage 

k The emission factor occurring during assembly, expressed in percentage 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

The refrigerant demand for new equipment is given by Equation (2.20) 

(2.20) 

Where, 

Sprod,i,t The national production of equipment for the application i at year t 

mi,t The average equipment charge for the application i at year t, expressed in kilograms 

The refrigerant demand for servicing is given by Equation (2.21) when the emission factor is 

applicable to the sector bank, and by Equation (2.22) in other cases. 

(2.21) 

Where, 

Elifetime i,t The total emissions as calculated by Equation (2.22) when the emission factor is 

applicable to the bank of the sector I 

* If the vintage requires servicing (2.22) 

Where, 

Eregular i,t_vintage Losses of vintage v since its last recharge until year t, if the vintage requires recharging, 

and for application I 

ηserv i,t The recovery efficiency at servicing at year t for application I 

RemaningCharge The remaining charge in the equipment at the moment of servicing being recovered 

Eirregular,t,i The irregular emissions at year t for application I 

The refrigerant demand for retrofit RRt corresponds to the amount of refrigerant being introduced into 

the system during the retrofit operation. 

The refrigerant demands calculated for each refrigerant and for each application, are added up to 

derive the national demand by refrigerant or the global demand. These demands are compared to the 

national declarations of refrigerant manufacturers and distributors or compared to the AFEAS sales 

data at the global level. 

Note: It has to be mentioned that AFEAS has decided to stop its yearly publication of refrigerant sales at the end 

of 2009, because the production of China, India, Russia, and Brazil are not published and so a bias between the 

“real” sales and the AFEAS data is becoming more and more significant. 

The cross-checks can be performed both on a country-by-country basis and globally. If the refrigerant 

inventories and the related emissions are adequately determined, the difference between the submitted 

figures and the calculated refrigerant sales will be small. If not, additional analyses are required. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

♦ Consistency for refrigerating equipment at the global level 

To reach high accuracy in the sizes of refrigerant inventories, the first step required is to gather 

reliable data for equipment numbers. Fortunately, annual statistical data are available for nearly all 

mass-produced equipment. Details on the availability of such numbers per application are provided in 

the corresponding chapters. When data is not available, correlations between sale population and 

wealth of countries are established to derive the missing data. Some data have been published by 

manufacturer associations, and some are available from marketing studies that can be purchased from 

specialised companies. The data on annual equipment sales allow deriving figures on production and 

sale at the national level for nearly all OECD countries, and also at the global level, when they are 

based on production data (see Figure 2.7). 

Cumulated Bank Refrigerant market Refrigerant market

(charged in new equip.) (charged in new equip.)

Parc Brand new equipment market Brand new equipment market

Refrigerant Refrigerant

market for market for

servicing

Aggregation by sector Aggregation by sector

Aggregation by refrigerant (HFC, HCFC, CFC) Aggregation by refrigerant (HFC, HCFC, CFC)

Global aggregation Global aggregation

Aggregation by country Aggregation by country

Figure 2.7 – Determination of refrigerant markets. 

As shown in Figure 2.7, the derivation of the global demand of refrigerants consists in: 

 establishing the annual sales of brand-new equipment and the amount of refrigerants charged in this 

equipment, 

 the derivation of refrigerants banked in the installed bases of the six sectors, as a function of their 

lifetime, 

 the calculation of the refrigerant market for servicing dependent on emission factors, 

 then the six application sectors are aggregated 

• by families of refrigerants, 

 country by country, 

 by country groups and globally. 
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order to determine refrigerant emissions. The 1990 to 2006 updating. 

ADEME/ARMINES Agreement 0874C0147– December 2009

References 

[ASH04a] Ashford, P., D. Clodic, A. McCulloch, L. Kuijpers, 2004a: Emission profiles from the 

foam and refrigeration sectors compared with atmospheric concentrations, part 1 - 

Methodology and data. International Journal of Refrigeration, 27(7), 687–700 

[ASH04b] Ashford, P., D. Clodic, A. McCulloch, L. Kuijpers, 2004b: Emission profiles from the 

foam and refrigeration sectors compared with atmospheric concentrations, part 2 - Results 

and discussion. International Journal of Refrigeration, 27(7), 701–716 

[ASH04c] Ashford, P., D. Clodic, A. McCulloch, L. Kuijpers, 2004c: Determination of Comparative 

HCFC and HFC Emission Profiles for the Foam and Refrigeration Sectors until 2015. 

Part 1: Refrigerant Emission Profiles (L. Palandre and D. Clodic, Armines, Paris, France, 

132 pp.), Part 2: Foam Sector (P. Ashford, Caleb Management Services, Bristol, UK, 238 

pp.), Part 3: Total Emissions and Global Atmospheric Concentrations (A. McCulloch, 

Marbury Technical Consulting, Comberbach, UK, 77 pp.). Reports prepared for the 

French ADEME and the US EPA 

[IPC00] IPCC. Good Practice Guidance and Uncertainty Management in National 

Greenhouse Gas Inventories. IPCC report, 2000 

[IPC05a] IPCC TEAP, 2005: IPCC/TEAP Special Report on Safeguarding the ozone Layer 

and the Global Climate System: Issues related to Hydrofluorocarbons and 

Perfluorocarbons. Prepared by Working Group I and III of the Intergovernmental 

Panel on Climate Change and the Technology and Economic Assessment Panel under the 

Montreal Protocol (Metz, B., L. Kuijpers, S. Solomon, S.O. Andersen, O. Davidson, J. 

Pons, D. de Jager, T. Kestin, M. Manning, and L.A. Meyer (editors). Cambridge 

University Press, Cambridge, UK, and New York, NY, USA, 488 pp. 

[IPC05b] IPCC/TEAP. Safeguarding the ozone layer and the global climate system - Issues 

related to hydrofluorocarbons and perfluorocarbons. IPCC/TEAP Special Report, 

Summary for Policymakers and Technical Summary, 2005 

[IPC06] Draft version of the Revised 2006 Guidelines for National Greenhouse Inventories: 

OECD / IEA Paris 

[IPCC96] Second Assessment Report of the IPCC, Working Group I, 1996 

[IPCC07] Fourth Assessment Report of the IPCC, Working Group I, The Scientific Basis, Errata 

Sheet, 2007 

[CLO05] CLODIC, Denis, PALANDRE, Lionel, BARRAULT, Stéphanie and ZOUGHAIB, 

Assaad. Inventories of the WorldWide Fleets of refrigerating and Air Conditioning 

equipment in order to determine refrigerant emissions: The 1990 to 2003 

Updating. Final report for ADEME, 2005. Confidential 

[MOP07] UNEP. Report of the Nineteenth Meeting of the Parties to the Montreal Protocol 

on Substances that Deplete the Ozone Layer. UNEP report, 17–21 September, 2007, 

Montreal, Canada, [CD Rom] 

[SAB09] SABA, S.,” Global inventories and direct emission estimations of greenhouse 

gases of refrigeration systems” Ph. D; Thesis Mines-Paristech December 2009

[TOC06] 2006 Report of the Refrigeration Air Conditioning and Heat Pumps Technical Option 

Committee. 2006 Assessment. UNEP Nairobi, Ozone Secretariat, February 2007 

[UNE05] UNEP, 2005: Supplement to the IPCC/TEAP Report, November 2005 
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34 

Appendix 1 

1 – Geographical split 

Global inventories cover six countries calculated independently and seven groups of countries: 

- USA, 

- China, 

- Japan, 

- Brazil, 

- India, 

- Canada, 

- Latin America and the Caribbean, 

- European Union 27 (EU27), 

- Other Europe, 

- West and Central Asia, 

- South and East Asia, 

- Oceania, and 

- Africa. 

The subdivision of the groups of countries is based on the geographical regions provided by the 

United Nations Statistics Division, revised on the 17th of October 2008 [UNS08]. However, the 

calculation assumptions (CFC and HCFC phase-out...) are not always identical over the countries 

within the same group. Therefore, some groups are separated in two subgroups in order to take into 

account the difference in the calculation assumptions. 

Table A2.1 provides details about the group subdivisions and the considered calculation assumptions. 

Calculations are led on one database for those groups that are not subdivided, i.e. the activity data of 

all countries constituting the group are aggregated in one database. Regions divided in two groups 

(Oceania, West and Central Asia, EU27, and Other Europe) are separated each in two different 

databases. 
 Page 35

35

Table A2.1 - Country groups description. 

Group Composition 

Assumptions for phase-out of 

CFCs and HCFCs 

Latin America and the 

Caribbean 

Antigua, Argentina, Bahamas, Barbados, Belize, Bolivia, 

Chile, Colombia, Costa Rica, Cuba, Dominica, Dominican 

Rep., Ecuador, El Salvador, Grenada, Guatemala, Guyana, 

Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, 

Paraguay, Peru, Saint Lucia, St Kitts and Nevis, St Vincent, 

Suriname, Trinidad & Tobago, Uruguay, Venezuela Article 5 

Africa 

Algeria, Angola, Benin, Botswana, Burkina, Burundi, 

Cameroon, Cape Verde, Centrafrica, Chad, Comoros, Congo 

, Congo RD, Côte d'Ivoire, Djibouti, Egypt, Eritrea, 

Ethiopia, Gabon, Gambia, Ghana, Guinea, Guinea Bissau, 

Guinea Eq, Kenya, Lesotho, Liberia, Libyan Arab, 

Jamahiriya, Madagascar, Malawi, Mali, Mauritania, 

Mauritius, Morocco, Mozambique, Namibia, Niger, Nigeria, 

Rwanda, Sao Tome, Senegal, Seychelles, Sierra Leone, 

Somalia, South Africa, Sudan, Swaziland, Tanzania, Togo, 

Tunisia, Uganda, Zambia, Zimbabwe Article 5 

West* and Central 

Asia 

Afghanistan, Armenia, Bahrain, Georgia, Iraq, Jordan, 

Kuwait, Kyrgyzstan, Lebanon, Oman, Qatar, Saudi Arabia, 

Syria, Turkmenistan, United Arab Emirates, , Yemen, 

Azerbaijan, Kazakhstan, Tajikistan, Uzbekistan Article 5 

 Turkey, Israel 

South and East Asia 

Bangladesh, Bhutan, Brunei, Cambodia, Indonesia, Islamic 

Republic of Iran, People's Democratic Republic of Korea, 

Republic of Korea , Lao, Malaysia, Maldives, Mongolia, 

Myanmar, Nepal, Pakistan, Philippines, Singapore, Sri 

Lanka, Thailand, Viet Nam Article 5 

Oceania Australia, New Zealand non Article 5 

 

Cook Islands, Fiji, Kiribati, Marshall, Micronesia, Nauru, 

Niue, Palau, Papua New Guinea, Samoa, Solomon Islands, 

Tonga, Tuvalu, Vanuatu Article 5 

EU 27 

EU 15: Austria, Belgium, Denmark, Finland, France, 

Germany , Greece, Ireland, Italy, Luxembourg, Netherlands, 

Portugal, Spain, Sweden, United kingdom non Article 5 

 

Other EU: Bulgaria, Cyprus, Czech republic, Estonia, 

Hungary, Latvia, Lithuania, Malta, Poland, Romania, 

Slovakia, Slovenia 

transition 

Article 5 -> non Article 5 

Other Europe 

Andorra, Belarus, Iceland, Lichtenstein, Monaco, Norway, 

Russian Federation, Switzerland, Ukraine non Article 5 

 

Albania, Bosnia and Herzegovina, Croatia, Moldova, 

Montenegro, Serbia , The Former Yugoslav Republic of 

Macedonia Article 5 

*Except Cyprus included in EU27 

[UNS08]: Composition of macro geographical (continental) regions, geographical sub-regions, and 

selected economic and other groupings, United Nations Statistics Division, Revised 17 

October 2008. http://unstats.un.org/unsd/methods/m49/m49regin.htm