T

he refrigeration and air conditioning industries

have undergone significant changes since the first

days of the Montreal Protocol and Clean Air Act.

H o w e v e r, our industry continues to change today,

because some of the regulations related to the re f r i g e r a n t

phaseout have not yet taken eff e c t .

Other regulations, such as the minimum SEER rating

for air conditioners, which had undergone lengthy litigation, have just now finally settled so we can begin to see

what its effects will be. The fact is, our industry has been,

and will continue to be in flux for some time to come.

In the U.S., the manufacture of CFCs was re q u i red by

law to be discontinued by the beginning of 1996, and

H C F C - 1 4 1 b1 by the beginning of 2003. We are now

p reparing for the next big step in the phaseout timetable:

Jan. 1, 2010. From that date on, U.S. system manufacture r s

will stop production of new equipment using HCFC-22.

Given how extensive the use of R-22 is in both re f r i g e r aPeering Into the Present

and Future of Refrigerants

Peering Into the Present

and Future of Refrigerants

H e re’s an overview of what’s happened thus far

with refrigerants and a look at current and pro j e c t e d

developments, including a couple that may surprise you

H e re’s an overview of what’s happened thus far

with refrigerants and a look at current and pro j e c t e d

developments, including a couple that may surprise you

BB YY GG UU SS RR OO LL OO TT TT II
tion and air conditioning, this will have a major impact.

L e t ’s look at what the industry has done so far in term s

of refrigerant development. The greatest portion of the

hvacr industry has used R-11, R-12, R-502 and R-22.

Some of the other refrigerants, such as R-500 or R-114,

w e re designed more for specific applications and, theref o re, were used in much smaller quantities compared to

R-12, R-502 and R-22.

Equipment oems extensively analyzed the diff e re n t

refrigerant alternatives available to them and settled on a

number of products. Once a new refrigerant had been

selected, they re - e n g i n e e red their equipment (not a trivial

p rocess by any means) and began manufacturing new

equipment for use with the new refrigerants. In these

cases, some clear winners emerg e d .

P re v i o u s l y, R-11 was used mostly in low-pre s s u re

chillers. The only substitute currently available is HCFC123, though its use has not been widely embraced by the

i n d u s t ry in spite of its clear benefits re g a rding re d u c e d

emissions and superior efficiency and perf o rm a n c e .

C o n c e rns for R-123 are its low level of toxicity (measu red as time weighted average or TWA) and the fact that,

being an HCFC, it might be scheduled for phaseout,

although at a later date than R-22. While the industry

continues to lobby legislators to allow the use of R-123

i n d e f i n i t e l y, some others have begun manufacturing systems using R-134a.

For most of the applications using R-12, HFC-134a

became the clear dominating choice. All auto air conditioning and medium- to high-temperature re f r i g e r a t i o n ,

especially in the appliance sector, have been using R-134a.

For medium- and low-temperature refrigeration applications previously using R-502, equipment oems for the

most part selected R-404A or R-507A2. Some decided to

use R-22 as a temporary solution due to its cost and the

availability of system components.

This is ironic since R-502 was originally designed to

replace R-22 in low-temperature refrigeration. In addition, R-410A, which so far has only been considered in air

conditioning, is now being tested as a potential re f r i g e r ation fluid as well.

F rom a technical point of view, R-410A works well in

the refrigeration range of temperatures, and it could even

have better capacity and efficiency than R-404A. However,

equipment redesign will be necessary to compensate for

the higher compressor discharge temperatures and the

higher operating pre s s u res. 

What would it take for R-410A to become a viable

option for refrigeration? It could be a combination of

factors: Regulations in the U.S. or in the European Union

(EU) making the use of R-404A more difficult due to global warming; marketing strategy from a compressor or system oem; or a market demand for one fluid instead of

two. At this point, R-410A is getting a hard look, and if

any company believes that it will gain an advantage over

the competition by using it, it may happen.

The choice of R-404A vs. R-507A has not been yet settled. R-404A is a three-component blend derived from the

two-component R-507A. The main diff e rence in composition is the addition of a small amount of R-134a to

R-404A to reduce its operating pre s s u re. Overall, sales of

R-404A are about four to five times those of R-507A. 

Most major refrigerant manufacturers and wholesalers

o ffer both refrigerants and most components are now

rated for both refrigerants as well. There is no technical

need for these two refrigerants because either one could

replace the other quite easily. The market, oems and contractors ultimately will have to select only one.

R e t rofit refrigerants emerge

While the oems decided what would be the next generation refrigerant for their new equipment, they could not

easily control what refrigerant went into equipment

a l ready in use. This created a whole new market in the

f o rm of the re t ro f i t s .

R e t rofit refrigerants are “interim” refrigerants used in

equipment designed for other refrigerants (the oem re f r i gerant), but still allow the equipment to operate. While oem

Mark Sullivan of Atofina’s Calvert City, Ky., plant labels

freshly painted R-22 cylinders. In time, the number of refrigerants should begin to consolidate to a select few.
refrigerants were few, re t rofit refrigerants were many.

Contractors and service techs became annoyed and

confused with the “re f r i g e r a n t - o f - t h e - d a y,” and complained about the number of cylinders they had to carry

in their vans to service re t rofitted units. After the dust settled, just a handful of re t rofit refrigerants, such as R-409A

and R-408A, that had been proven to work well and were

o ff e red by a number of reputable companies, maintained

a considerable position in the marketplace. In any case,

the heyday for re t rofits from R-12 and R-502 has passed,

although a healthy market still re m a i n s .

The next refrigerant to be phased out in the U.S. is

R-22. Because of R-22’s use in both the re f r i g e r a t i o n

and air-conditioning sectors, more than one re p l a c e m e n t

refrigerant will be needed to replace it entire l y.

In the refrigeration market, R-22 is being substituted

with R-404A/R-507A. In the air-conditioning market,

mostly in the residential and light commercial sectors,

R-410A is the leading candidate. Keep in mind that while

these new refrigerant substitutes are currently available,

and many companies are making

equipment and components for

them, R-22 can be used for equipment service indefinitely.

It would seem logical to assume

that a need to re t rofit R-22 equipment would not develop until 2010

or later, especially considering that

R-22 will continue to be pro d u c e d

for service until 2020. However, in

the hvacr market, logic may have

nothing to do with re a l i t y, since a

small market for re t rofits appears

to have begun re c e n t l y.

T h e re are several reasons for

this development. First is the need of some industry sectors

to be more “green” due to international pre s s u re from environmental groups. Next are doomsday predictions about

R-22 shortages and price increases. Third is the U.S.

E n v i ronmental Protection Agency’s (EPA) intention to

redistribute allocations for the pro d u c t i o n / i m p o rtation of

HCFCs in 2009, creating uncert a i n t y.

F i n a l l y, EPA’s heavy refrigerant emission fines coupled

with an offer to reduce or eliminate some fines if ozonedepleting substances (ODS) were completely eliminated

ahead of schedule – such as in the bakery and superm a rket industries – are additional reasons for an emerg i n g

R-22 re t rofit market.

T h e re are a number of refrigerants that can be used as

re t rofits for R-22, depending in part on the application. In

refrigeration, refrigerants such as R-404A/R-507A, R-407C

and R-417A are being mentioned, with the last one promoted as a drop-in. For air conditioning, only R-407C or

R-417A are mentioned.

Our lab data, as well as that of several other independent testing facilities, show that while the fluids will work

a d e q u a t e l y, none will match the perf o rmance of R-22.

R-404A and R-407C is the closest in perf o rmance, but

re q u i res an oil change to a polyol ester (POE) oil.

R-417A makers claim the refrigerant works with the

c u rrent oil in the system, but at the cost of a perf o rm a n c e

loss. In all cases, re t rofitting will force the end user to

c o m p romise. Note that R-410A, the leading oem re f r i g e rant, is not a re t rofit candidate because its much higher

operating pre s s u res are not compatible with the design of

R-22 systems.

What about the others?

T h ree other refrigerants are worthy of discussion: hydrocarbons (HC), ammonia (NH3) and carbon dioxide (CO2) .

They have all been used, or are currently in use, in hvacr.

These refrigerants are viewed as “green” or at least “gre e n e r ”

than current HFC choices, especially with re g a rd to global

w a rming. Additionally, recently proposed legislation in the

EU may make some of them more popular there .

H y d rocarbons have been used for a few years in re f r i gerators, competing for market share

with R-134a in some EU member

states. However, they have not been

used in the U.S. Hydrocarbons are

relatively inexpensive, compatible

with mineral oil and have a low

d i rect global warming potential.

On the down side, they are highly

flammable and their use is severe l y

restricted by building and fire codes

a c ross the U.S. Additionally, their use

i n c reases equipment cost (to eliminate all possible ignition sourc e s )

and their overall global warm i n g

index (direct and indire c t )4 is comparable and, in many cases, worse than that of applicable

HFCs. Hydrocarbons will probably get very little use, if

a n y, in the U.S.

Ammonia has been used for many years. It is best suited for relatively large applications such as industrial

p rocess cooling where it appears to have seen small

g rowth. Ammonia exhibits good thermodynamic pro p e rties and low direct global warming potential.

Its use is limited by its incompatibility with copper, a

common material used in refrigerant lines and heat

exchangers, and by its flammability and toxicity rating

of B2 by ASHRAE’s Standard 34. Its use also is limited

by building and fire codes, so it is best applied in re l a t i v e l y

remote locations where it can be contained easily or where

its release would not affect surrounding populations.

Carbon dioxide (CO2) is not used much in commerc i a l

applications today, although it was used many years ago

b e f o re being displaced by refrigerants such as CFCs. CO2

has seen a strong re s u rgence due to several European car

m a n u f a c t u rers’ interest in using it to replace R-134a in

mobile air conditioning (MAC), mostly for enviro n m e n t a l
reasons linked to global warm i n g .

C O2 o ffers a very low direct global warming potential

and comparable perf o rmance to R-134a systems. It perf o rms better than R-134a in the heating mode of heat

pump applications.

The downsides for CO2 a re the extremely high operating pre s s u res (approximately 10 times those of R-134a),

g reater system weight and cost than a comparable R-134a

system and poor perf o rmance at higher ambient temperat u res (greater than 90° F). Overall, CO2 is thought to be

slightly inferior or comparable to enhanced R-134a automobile a/c systems based on TEWI.

T h e re is legislation pending before the Euro p e a n

Commission parliament that proposes the banning of

R-134a in auto a/c systems beginning with some new 2009

models and all models in 2011. This legislation, which

appears to be based only on the re f r i g e r a n t ’s direct global

w a rming value, would only allow the use of CO2 in auto

a/c systems after R-134a. The current draft of the legislation also excludes R-152a, a flammable HFC.

At this point, even though much wider proposed legislation affecting R-134a was defeated in Europe, the future

of R-134a in auto a/c is still unclear. Automakers seem to

be balking at the high cost to convert production to CO2,

especially after the estimated $5 billion-plus (in U.S. dollars) price tag of converting from R-12 to R-134a just a

few years ago.

After eight years of the CFC phaseout and with only six

years until the HCFC phaseout, it is still not clear or certain which refrigerants are here to stay. For the U.S. at

least, it looks like R-134a, R-404A/R-507A and R-410A are

p retty sure bets.◆

Gus Rolotti is technical and applications lab manager, King

of Prussia Technical Center, Atofina Chemicals Inc. For

m o re information, visit forane.com or atofinachemicals.com.

F o o t n o t e s

1. While R-141b had limited use as a refrigerant, its earlier phase out avoided a drastic reduction in R-22 pro d u ction, which would have directly impacted the hvacr sector

m o re dire c t l y.

2. The ASHRAE Standard 34 designation for this re f r i g e rant is R-507A; R-507 also is accepted and used.

3. This is measured as total equivalent warming index

(TEWI) or life cycle climate perf o rmance (LCCP). Both

TEWI and LCCP take into account the direct and the indirect portion of a refrigerant by considering factors such as

e ff i c i e n c y, energy used and end-of-life disposal.