Decarbonizing HVAC and 

Water Heating in 

Commercial Buildings

NOVEMBER 2021
Learn more at betterbuildingssolutioncenter.energy.gov

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Table of Contents

Introduction 2

1. Electrification Options for HVAC and Water Heating 3

2. Evaluation Checklist for Electrification Assessment 9

3. Industry Transition to Low-GWP Refrigerants 11

4. Selected Resources for Facility Owners 13
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Introduction 

Electrification of building loads present a significant opportunity to reduce site-level greenhouse gas (GHG) 

emissions, especially when combined with renewable and zero-carbon electricity resources. Electrification 

involves the conversion of a building system that would traditionally use fossil fuels (such as, natural gas, 

fuel oil, or propane) to the use of electrical power, which could be a key strategy in decarbonization. This 

guidance document is intended to provide building owners and facilities engineers with heating options 

and design considerations, as well as additional resources on key topics. The document focuses on 

electrification and decarbonization of space heating and water heating loads using electric heat 

pump systems.

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This resource can be used as a starting point when conducting the technical, economic, and feasibility 

assessment for converting to all-electric heating solutions. The attractiveness of facility electrification 

will vary substantially by region, climate, utility rates, existing systems, and other factors. While any of 

these strategies can be considered for new construction, this publication focuses on applying heat 

pumps to existing facilities. Key considerations for existing buildings include: Technology availability 

and performance.

 Technology availability and performance.

 Upfront, annual, and lifecycle costs

 GHG emissions today, and in future years (e.g., anticipated renewable energy procurement, utility supplier and 

state renewable commitments)

 Infrastructure impacts (e.g., avoided installation, replacement, or repair of gas piping; building envelope/heating 

distribution system capabilities; electrical panel and wiring upgrades; fuel storage inspection, maintenance, 

and decommissioning)

 Reliability and resiliency (e.g., backup heating systems and storage needs)

This resource is organized into four sections: 

1. Electrification Options for HVAC and Water Heating

2. Evaluation Checklist for Electrification Assessment

3. Industry Transition to Low-GWP Refrigerants

4. Selected Resources for Facility Owners

Better Buildings has additional resources and support for owners working toward low-carbon buildings at 

the Decarbonization Resource Hub.

1 This video from the Solar Decathlon Building Science Education Series provides an overview of heat pump 

operations and electrifying commercial heating systems.
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1. Electrification Options for HVAC and Water Heating

Residential, commercial, and industrial facilities use a wide variety of HVAC and water heating 

technologies. While heat pump solutions are readily available for some equipment types and system 

designs (e.g., commercial rooftop units below 25 tons), facilities relying on boilers and distributed heating 

systems as well as those in colder climates have more limited options. 

Heat pumps are often classified by their heat source (e.g., air-, water-, and ground-source) and thermal 

distribution method in the building (e.g., air for packaged rooftop units, water for hydronic heat pumps, and 

refrigerant for variable refrigerant flow solutions). As U.S. market interest in heat pumps has increased in 

recent years, manufacturers and system designers continue to develop new strategies to electrify new and 

existing facilities. 

This section describes heat pump retrofit options and key considerations for the following HVAC and water 

heating system designs common to commercial buildings. 

HVAC Systems Water Heating Systems

 Gas-fired packaged rooftop units

 Split system air conditioners and gas furnaces

 Boiler systems

 Air handlers with reheat and/or perimeter 

space heating

 Campus/district chilled water and steam systems

 Packaged Terminal Air Conditioners (PTAC)

 Gas-fired unit heaters, radiant wall heaters, and 

other heating systems 

 Ventilation make-up air units

 Gas hot water boiler for central domestic 

hot water

 Gas or electric resistance water heaters

 Small electric storage or point-of-use systems
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HVAC (Space Heating, Ventilation, and Air Conditioning) System Retrofits

Existing System Heat Pump Retrofit Options Key Considerations

Gas-fired 

packaged rooftop 

units (RTUs)

 Heat pump RTU: Most major manufacturers offer airsource heat pump RTUs in capacities of 3-25 tons, with 

optional auxiliary heating provided by electric 

resistance coils.

 Dual fuel heat pump RTU: A few manufacturers offer dual 

fuel heat pump RTUs which operate the heat pump to 

around 17°F and then switch over to an integrated gas 

furnace for colder temperatures. 

 Variable Refrigerant Flow (VRF) system: VRF systems 

use heat pumps in each zone to provide heating and 

cooling and modulate the amount of refrigerant sent to 

each zone. For existing buildings with RTUs, a VRF system 

is a significant HVAC redesign and retrofit.

 Water-to-air heat pumps: Water can be conditioned with a 

ground loop or a separate air-to-water heat pump.

 Some heat pump models report heating capacity 0°F to 

10°F, although there is no standardized cold-climate 

specification for RTUs or VRF systems. 

 When available, dual fuel heat pump RTUs are a relatively 

straightforward retrofit for gas-fired RTUs. 

Split-system ACs 

and gas furnaces

 Ducted split system heat pump: Split system AC and gas 

furnace heating can be replaced with a ducted split system 

heat pump. The furnace may continue to be utilized for the 

supply fan and for back-up heating.

 Ductless mini-split heat pump: Split system AC and 

gas furnace heating can be replaced with a non-ducted 

split-system heat pump (ductless mini-split). The gas 

furnace and ductwork can be removed if it is not used for 

back-up heating.

 Split-system heat pumps are available for both residential 

(1-5 ton) and light commercial (6-20 ton) capacities, 

although cold-climate certifications are only available for 

residential-style models. Cold-climate heat pump solutions 

are available for residential capacities (up to 5 tons) and 

can operate down to -15°F.

 Larger furnaces/air handling units (AHUs) may not have 

direct heat pump equivalent. Heat pump replacement of 

larger capacity furnaces/AHUs may have space constraints 

(i.e., mechanical closet size).
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Existing System Heat Pump Retrofit Options Key Considerations

Boilers: 

low temperature 

(110°F to 140°F), 

medium 

temperature 

(150°F to 180°F), 

and steam systems

 Air-to-water and water-to-water heat pumps can generate 

hot water in the range of 110-140°F and come in a variety 

of configurations and modular capacities to meet the 

building needs. Some products also provide chilled water 

as a byproduct and may be called heat pump chillers. 

 Heat recovery chillers are a good solution where 

simultaneous chilled water and hot water loads are 

common throughout the year. The heat generated during 

the chilled water cycle can be used for space heating or 

domestic hot water loads rather than being rejected to the 

outdoor air, which significantly improves overall system 

efficiency. With heat recovery chillers, the heating is a 

byproduct of the chilled water production (e.g., “you get 

what you get” for hot water). 

 VRF or distributed ductless split-system systems are 

another electrification option for buildings with legacy boiler 

systems, especially if the building previously used window 

AC or no AC system. This system requires full redesign of 

the building’s HVAC system and decommissioning the 

hydronic piping. 

 Most systems provide lower hot water supply temperatures 

(110°F -140°F) than traditional boilers. Buildings may 

require weatherization to reduce heating loads and radiator 

redesign to meet building heating needs without replacing 

hot water piping.

 Hydronic heat pump products are available in a range of 

capacities and configurations and are often designed to 

connect as modular units to achieve higher capacities. 

 Systems may include thermal storage tanks to provide 

buffer capacity during periods of high demand or during 

defrost cycles. 

 Comparisons of size, weight, and installation complexity to 

conventional boiler and chiller systems will vary. 

 Limited design experience and demonstrations in U.S., 

particularly for retrofit applications when completely 

replacing gas-fired boiler systems. Auxiliary electric 

resistance or gas-fired boilers may be needed for 

colder climates.

 Review utility rate structures (especially if electric 

resistance is used) due to demand charge impacts.
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Existing System Heat Pump Retrofit Options Key Considerations

AHUs with reheat 

and/or perimeter 

space heating

 If the AHUs or Variable Air Volume (VAV) boxes are 

supplied by a hydronic loop with a gas-fired boiler, consider 

hydronic heat pump solutions described above.

 If the system would operate exclusively in either space 

cooling or space heating mode, manufacturers offer AHUs 

that contain water-to-air heat pumps. 

 If the AHUs or VAV boxes currently use electric resistance 

heating elements, this strategy would already support 

heating electrification goals, but additional energy efficiency 

measures (e.g., envelope improvements) would be 

advisable to minimize the amount of electric resistance 

heating used. 

 Major renovation projects could consider conversion to 

VRF, or ground-source heat pumps (GSHP) options.

 Electric resistance baseboards and VAV electric resistance 

reheat should not be the primary building heat source for 

high-efficiency buildings.

 Consider strategies to minimize the amount of reheat 

needed to serve individual building zones. Strategies could 

include improved controls to balance supply air conditions, 

incorporating auxiliary cooling solutions to address problem 

zones, or using higher supply air temperatures coupled with 

a central dehumidifier.

Campus/district 

chilled water and 

steam systems

 Campus/ district chilled water/ steam systems for heating, 

cooling, and often electric generation.

 Transition buildings from steam or medium temperature 

hot water (over 160°F) to low temperature hot water 

(less than 140°F).

 Use large heat recovery chillers to generate hot and 

cold water.

 Use a centralized well field with large centralized 

hydronic heat pumps that distribute hot or cold water to 

each building or an ambient hydronic loop between the 

well field and buildings with water-source heat pumps at 

each building. 

 Another opportunity is to transition individual buildings from 

the campus or district energy system to a decentralized 

system with heat pumps located at each building.

 Few case studies and analyses have been done to 

evaluate the energy, cost, and emissions impacts with 

campus-wide heat recovery chillers and/or a decentralized 

heat pump strategy.

 Conversion to a low temperature piping network requires 

updates to building distribution systems as well as larger 

central system piping. 

 Moving to a decentralized system may present space 

constraints at each building.
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Existing System Heat Pump Retrofit Options Key Considerations

PTAC (Packaged 

Terminal Air 

Conditioner)

 Most PTAC manufacturers offer heat pump models 

known as Packaged Terminal Heat Pumps (PTHP), 

and these products typically include electric resistance 

backup heating.

 At least one manufacturer offers a PTHP product that can 

operate to below zero conditions.

 Major renovation projects could consider switching from 

PTAC/PTHP system designs to VRF or other options.

 Very limited availability of cold-climate PTHPs and there is 

currently no standardized cold-climate specification for 

PTHPs.

 New ventilation requirements (ASHRAE 62.1) prohibit 

under door ventilation and require PTHPs to provide 

dehumidified ‘makeup’ air. In cold climates this can be 

highly energy intensive. Ventilation requirement can be 

fulfilled by a secondary system such as a Dedicated 

Outdoor Air System (DOAS).

Gas-fired unit 

heaters, radiant 

heaters, and other 

miscellaneous 

heating systems

 Electric resistance and electric radiant options are available 

for most miscellaneous gas-fired heating categories, and 

conversions may require some electrical upgrades and/or 

system redesign.

 Consider installing ductless split-system heat pumps, VRF, 

and PTHPs in place of or in combination with electric 

resistance and radiant options.

 Electrifying building heating systems with non-centralized 

heating systems is an emerging area of HVAC design.

Ventilation makeup air units

 Heat pump options are available for some make-up air 

units and dedicated outdoor air systems; electric resistance 

heating elements may be used.

 Rate of makeup air (cfm) and anticipated outdoor conditions 

will dictate retrofit selection. 
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Domestic/Service Water Heating System Retrofits

Existing System Heat Pump Retrofit Options Key Considerations

Gas hot water 

boiler for central 

domestic hot water 

(DHW)

 Manufacturers have started offering both integrated and 

split-system heat pump water heaters (HPWH) with higher 

capacity and supply temperatures for high demand 

commercial applications, although these have high 

installed costs. 

 Like space heating boilers, some air-to-water or water-towater heat pumps and heat recovery chillers can provide 

domestic hot water.

 If necessary, electric resistance booster heaters can 

supplement the HPWH to achieve higher temperatures.

 Building-level sewer heat recovery systems can be used for 

domestic hot water. Campus- or city-level systems can be 

used for space conditioning.

 Cost of HPWH solutions may be considerably more expensive 

than gas-fired solutions.

 Availability/sizes of HPWH: limited availability of 

comparative HPWH systems that can meet the capacity and 

recovery needs.

 Recovery rate of HPWH: Commercial buildings with high hot 

water loads (e.g., food service, lodging, gyms, dormitories, 

healthcare) typically have large storage water heaters with 

high recovery rates, which favors gas due to faster recovery. 

Size of heat pump and storage need to be matched to 

anticipated loads to ensure sufficient hot water and 

good recovery.

Gas or Electric 

resistance water 

heater for smaller 

DHW applications

 Similar to the above, more manufacturers are offering

both unitary and split-system HPWHs for the light 

commercial market.

 Some applications could use residential-style HPWHs.

 Instantaneous electric water heater for small hot water 

loads (point-of-use) and eliminate recirculation pumping.

 Residential and light commercial HPWHs are available 

today from major manufacturers with storage capacities of 

40-120 gallons.

 Most HPWHs require a 220V electrical line, but it is anticipated 

that 110V models will be available soon.

Small Electric 

Storage/ Point-ofUse systems

 Small electric storage or instantaneous electric water 

heaters are common for building types and applications 

with relatively low hot water loads (e.g., office sinks).

 These systems are unlikely to convert to heat pump systems 

due to technical, economic, or physical feasibility constraints.
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2. Evaluation Checklist for Electrification Assessment

As described in the previous tables, there are a wide variety of heating electrification options available and 

challenges to consider when evaluating opportunities for specific facilities. This section outlines some 

additional topics to evaluate when performing a site electrification assessment. 

 Placement of All-Electric Systems: Heat pump systems may have a larger footprint than the existing fuel-fired 

systems and may require larger hot water storage tanks. During the site assessment, the team should evaluate 

the available floor or roof space that would be available for the heat pump systems and necessary heat 

exchangers. In addition, many newer rooftop units have larger footprints than older models and may require 

roof curb redesign or structural supports to accommodate the larger size and weight. Air-based systems need 

large quantities of outside air to exchange heat, which often requires outdoor placement of units (rooftop or 

ground mount). 

 Electrical Service, Panels, and Wiring: Conversion to all-electric systems may require some redesign or 

upgrade of the facility’s electrical panels and wiring, especially for older buildings where electrical upgrades 

have not been performed recently. On the smaller end, this may include running a dedicated electrical line for a 

HPWH. On the larger end, this may involve an upgrade of the electrical service line from the utility as well as 

panel and wiring upgrades within the building. Most commercial buildings should have excess electrical 

capacity available, especially if they have existing space cooling systems, but an evaluation of the new power 

requirements and available electrical capacity will confirm whether upgrades are needed. In addition, the new 

electrical loads may change the electrical rate class or the monthly demand charges for the building and 

should be evaluated. If it appears that extensive upgrades or utility rate changes would be necessary, the 

team could consider incorporating on-site renewable generation, battery storage, building envelope and 

window improvements, lighting retrofits, and other energy efficiency measures to mitigate the increase in 

electrical demand. 

 Thermal Distribution Systems: Facilities using high temperature steam or hot water distribution (180°F and 

above) should evaluate whether there is sufficient radiator and heat exchanger capacity to accommodate the 

lower supply temperatures of hydronic heat pumps (often 110-140°F). In some cases, the existing distribution 

system is oversized and would have sufficient capacity for the lower temperatures, especially if the building 

envelope is upgraded to lower the heating load. In other cases, decommissioning the steam/hydronic system 

and transitioning to a VRF system may be preferable if there were leakage and other problems with the existing 

distribution system. 

 GSHP Solutions: GSHPs are an attractive electrification strategy due to their strong performance and efficiency 

throughout the year, even in extreme cold weather. GSHPs can make sense for both new and existing 

applications if the heating and cooling loads are balanced through most of the year to make the most benefit of 

the ground wells. For retrofit, land is required for the well field; a combination well and air-based system can 

also be considered.
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 Central vs. Distributed Solutions: Many buildings today use large, centralized space and water heating 

systems, which may pose technical or feasibility challenges for electrification projects. If the project is part of a 

larger renovation, the team may consider moving towards a decentralized strategy where smaller heat pump 

and electric resistance systems are placed throughout the building. For example, if a large gas-fired boiler 

previously provided both space and water heating to the building, the team could consider separate systems for 

space heating and water heating or placing individual heat pump or point-of-use water heaters throughout the 

building. Ductless mini-split heat pumps are also effective distributed solutions where only a small area of the 

building requires thermal conditioning (for example, an office in a warehouse) or if an area is significantly 

warmer or cooler than other parts of the building. 

 Auxiliary and Back-up Systems: The heating capacity and efficiency for air-source heat pumps decreases at 

colder temperatures, which requires careful consideration for peak day capacity needs including during defrost 

cycles. Ideally, choose heat pumps that will operate at the coldest possible temperatures for the location to 

satisfy the building’s heating loads. For small amounts of backup capacity, thermal storage can be used to cover 

a few hours when the heat pump is in defrost mode or during extreme cold if feasible at the site. If the electric 

system is replacing a fossil fuel system, the fossil fuel may be used as a backup for extreme cold days. Electric 

resistance is common for all-electric heating solutions but has much lower efficiency and higher operating costs 

than heat pump operation. Electric resistance back-up systems should be designed to operate sparingly (for 

example, during defrost cycles) and carefully sized to minimize potential electrical capacity upgrades. 

 Review Available Utility and State Incentives: Many electric utilities and state energy efficiency programs 

offer financial incentives and rebates to support the installation of high-efficiency electric technologies. In some 

cases, utilities offer additional incentives for early replacement and fuel-switching projects. For complex projects 

or technologies that are not listed in the incentive programs, the team should communicate with the energy 

efficiency program to understand the custom application process. Furthermore, electric technologies can 

participate in demand response and load flexibility programs, particularly those technologies that utilize hot 

water storage systems. 
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3. Industry Transition to Low-GWP Refrigerants

Electric heat pump technologies contribute to a facility's GHG emissions through both their energy 

consumption and their refrigerant usage. Refrigerants are the primary working fluid for most current 

building air conditioning, heat pump, and refrigeration systems, with most systems using a class of 

refrigerants known as hydrofluorocarbons (HFCs). HFCs have zero ozone-depletion potential (ODP), but 

high global warming potential (GWP), which is why global policymakers and HVAC&R industry 

stakeholders are transitioning to refrigerants with lower GWP values. For many equipment categories, 

refrigerant leakage occurs slowly over the system lifetime and service technicians must periodically replace 

it. In addition, refrigerant leakage can occur during system decommissioning if the refrigerant is not 

recovered properly. These issues are more prevalent in split-systems with field installed piping and less 

prevalent for factory sealed systems and those returned to a facility that can decommission the equipment. 

Minimizing field installation of refrigerant lines and refrigerant tends to result in less leakage and fewer 

long-term maintenance issues.

The table below summarizes low-GWP alternatives under consideration for major space heating and water 

heating sectors. All major HVAC and water heating equipment categories have promising low-GWP 

alternatives, although refrigerant approval and product availability may still be under development. LowGWP options under consideration will typically share similar characteristics to the high-GWP refrigerant 

targeted for replacement, except for potentially flammability and toxicity properties. Some low-GWP 

refrigerants offer energy efficiency and performance benefits over HFC technologies (e.g., HPWHs using 

CO2 [R-744]). 

Many low-GWP options are readily available in global markets, but are waiting for U.S. Environmental 

Protection Agency (EPA) Significant New Alternatives Policy (SNAP) program approval and state building 

code updates before adoption in new systems in the U.S. Other low-GWP refrigerants are subject to EPA 

SNAP charge limits due to flammability risks (i.e., labelled as A3 or A2L under ASHRAE Standard 34), 

which prevents their use in higher capacity applications. 

Very few alternative refrigerants are direct drop-in replacements for HVAC&R and other end-use sectors, 

which can pose challenges to adoption because the only alternative is a full system replacement. Even in 

instances where an alternate refrigerants’ properties are similar, systems may require some redesign and 

component upgrades to manage flammability risks.
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Current and Alternative Refrigerants for HVAC and Water Heating Applications 

Category Current HFC 

(100-year GWP)

Promising Low-GWP 

Alternative (GWP, Class)* U.S. Approval Status

Residential 

HVAC

R-410A (2,088) R-32 (675, A2L)

R-466A (733, A1)

R-454B (466, A2L)

R-290 (3, A3)

 Alternative refrigerants are generally not available in the U.S. today for central 

split-system, ductless split-system, geothermal AC/HP, rooftop unit, and VRF 

systems, but will be available in the next several years.

 R-32 and R-290 are approved for use in room/window AC/HP and PTAC/PTHP 

systems in the U.S. HVAC manufacturers have announced plans for offering 

products using A2L refrigerants (e.g., R-454B, R-32) in the coming years. 

 EPA SNAP Rule 23 (May 2021) approved several new A2L alternatives subject 

to use restrictions. 

 State and local building code updates would be necessary for flammable A2L 

and A3 refrigerants in most states. 

 California and Oregon have passed regulations requiring low-GWP refrigerants 

(<750 GWP) starting in 2025. 

 The industry expects a similar national transition to occur nationally around 2025

Commercial 

HVAC

R-410A (2,088)

R-134a (1,430)

R-32 (675, A2L),

R-466A (733, A1)

R-454B (466, A2L)

R-450A (604, A2L)

R-513A (631, A2L)

R-290 (3, A3)

R-600a (3, A3)

Chillers (small 

to medium)

R-410A (2,088) R-32 (675, A2L),

R-466A (733, A2L)

R-454B (466, A1)

R-450A (604, A1)

R-513A (631, A1)

R-717 (0, B2L)

 Alternative refrigerants that are approved for use in the U.S. are R-744 (A1), R717, R-450A (A1), R-513A (A1), and R-1234ze (A2L)

 HVAC manufacturers offer products today using low-GWP refrigerants and 

several states have already restricted the use of chillers using high-GWP 

refrigerants.

Chillers (large) R-134a (1,430) R-1234yf (4, A2L),

R-1234ze (7, A2L)

Water Heating R-134a (1,430) R-1234yf (4, A2L)

R-1234ze (7, A2L)

R-744 (1, A1)

 High-efficiency systems using R-744 are commercially available in heat pump 

water heating applications.

*ASHRAE Standard 34 classifies new refrigerants based on flammability and toxicity. Toxicity Groups: A – Nontoxic, B – Toxic. Flammability Classes: 1 – No flame propagation 

(i.e., non-flammable), 2L – Lower flammability 2 – Flammable, 3 – Higher flammability
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4. Selected Resources for Facility Owners

The table below provides a list of available research literature and case studies that focus on heating 

electrification and decarbonization of commercial buildings. Most building decarbonization analyses focus 

on the single-family residential sector, with fewer studies providing extensive analysis on the 

decarbonization feasibility for commercial, large multifamily, and industrial facilities. The following 

resources may be useful to examine specific building subsegments and technologies in greater detail.

Selected Electrification Resources and Case Studies

Title Topic Areas Case Studies Notes

Thermal 

Electrification of 

Large Buildings 

in the 

Commonwealth

(A Better City/ 

Cadmus, 2020)

 Large multifamily and 

commercial buildings 

 Space heating and water 

heating

Yes, several 

real-world 

case studies

The report provides an overview of heating 

electrification options in Massachusetts, 

with several case studies for new 

construction and retrofits, including those 

with boiler systems.

Zero Carbon 

Commercial and 

Multifamily

Construction 

(Redwood 

Energy, 2019)

 Two reports, one for large 

commercial and one for 

multifamily (mostly new 

construction)

 Space heating, water 

heating, cooking, and 

transportation 

electrification

Yes, several 

real-world 

case studies

The guide contains examples of large new 

commercial and multifamily developments 

that have avoided fossil fuel use in favor of 

all-electric designs and provides examples 

for specific all-electric technologies.

Heat Pump 

Retrofit 

Strategies for 

Multifamily 

Buildings

(NRDC, 2019)

 Residential multifamily, 

both small and large (may 

have applicability for some 

commercial as well)

 Space heating and water 

heating, both in-unit and 

central

Yes, for 

several 

prototypical 

retrofit 

projects

The report examines heating electrification 

options for multifamily buildings, with a 

particular focus on technology options for 

existing buildings with central steam and 

hot water systems.
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14

University of 

California 

Strategies for 

Decarbonization: 

Replacing 

Natural Gas

(IEE, NCEAS, 

Univ of 

California, 2018)

 Focus on large commercial 

buildings, particularly those 

on campus district energy 

systems

 Space heating, water 

heating, CHP, and process 

loads

Yes, some 

real-world 

examples and 

some 

feasibility 

analysis

The report examines strategies to 

decarbonize the University of California 

campuses, many of which use gas-fired 

central energy plants for electricity 

generation, and district heating and 

cooling. It focuses on complimentary 

solutions including deep energy efficiency, 

biogas, electrification, and the synergies 

with energy storage in the campus setting.

Advanced 

Energy Design 

Guides: 

Achieving Zero 

Energy Series

(ASHRAE)

Guides available for:

 Small to medium offices 

(2019) 

 K-12 schools (2018) 

 Multifamily (Coming 2021)

Yes The guides offer contractors and designers 

the tools, including recommendations for 

practical products and off-the-shelf 

technology, needed for achieving a zeroenergy building. Mechanical 

recommendations in chapter 5 provide 

insights on heat pumps.

AHRI Directory 

of Certified 

Product 

Performance

 Performance database for 

a variety of HVAC and 

water heating products

No This is the HVAC/WH industry’s central 

resource for certified performance data for 

new equipment. 

NEEP 

Residential Cold 

Climate ASHP 

Product List

 Performance database for 

residential ducted and nonducted air-source heat 

pumps meeting NEEP’s 

cold-climate specification

No The current NEEP specification focuses on 

residential cold-climate heat pumps (up to 

~6 tons). Other equipment categories may 

be considered in the future.
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DOE/EE-2525