Substitutes in Residential and Light Commercial Air Conditioning and Heat Pumps
Substitutes are reviewed on the basis of environmental and health risks, including factors such as ozone depletion potential, global warming potential, toxicity, flammability, and exposure potential. Lists of acceptableThis designation means that a substitute may be used, without restriction, to replace the relevant ODS within the end-use specified. For example, HCFC-22 is an acceptable substitute for R-502 in industrial process refrigeration. Note that all SNAP determinations apply to the use of a specific product as a substitute for a specific ODS in a specific end-use. and unacceptableThis designation means that it is illegal to use a product as a substitute for an ODS in a specific end-use. For example, HCFC-141b is an unacceptable substitute for CFC-11 in building chillers. Note that all SNAP determinations apply to the use of a specific product as a substitute for a specific ODS in a specific end-use. substitutes are updated several times each year. The list of substitutes is shown below.
Many acceptable substitutes under SNAP may be restricted under the Technology Transitions Program. Find more information on Technology Transitions Program restrictions.
Note: SNAP-related information published in the Federal Register takes precedence over all information on this page.
| Substitute | Trade Name(s) | Retrofit/ New | GWPThe index used to translate the level of emissions of various gases into a common measure in order to compare the relative radiative forcing of different gases without directly calculating the changes in atmospheric concentrations. GWPs are calculated as the ratio of the radiative forcing that would result from the emissions of one kilogram of a greenhouse gas to that from the emission of one kilogram of carbon dioxide over a period of time (usually 100 years). Gases involved in complex atmospheric chemical processes have not been assigned GWPs. See lifetime. | ASHRAEASHRAE is an international organization that establishes standards for the uniform testing and rating of heating, ventilation, air conditioning, and refrigeration equipment. It also conducts related research, disseminates publications, and provides continuing education to its members. Designation (Safety Classification) | SNAP Listing Date | Listing Status | |
|---|---|---|---|---|---|---|---|
| Ammonia Absorption | N | 0 | 0 | B2 | September 5, 1996 | Acceptable | |
| Desiccant Cooling | N | 0 | N/A | N/A | September 5, 1996; June 16, 2010 (pdf) (229 KB) | Acceptable | |
| Evaporative Cooling | N | 0 | N/A | N/A | September 5, 1996 | Acceptable | |
| HFC-134a | R/N | 0 | 1,430 | A1 | June 16, 2010 (pdf) (229 KB); July 21, 2017 (pdf) (314 KB) | Acceptable | |
| HFC-32 | N | 0 | 675 | A2L | April 10, 2015 (pdf) (769 KB); May 6, 2021 (pdf) (583 KB); April 28, 2023 (pdf) (584 KB) | Acceptable with Use Conditions: See rules for detailed conditions. | |
| R-417C | Hot Shot 2 | R | 0 | 1,820 | A1 | October 4, 2011 (pdf) (201 KB) | Acceptable |
| R-125/R-134a/R-600a (28.1/70.0/1.9) | NU-22 old composition | R/N | 0 | 1,990 | A1 | June 16, 2010 (pdf) (229 KB) | Acceptable |
| R-125/R-290/R-134a/R-600a (55.0/1.0/42.5/1.5) | ICOR AT-22 | R/N | 0 | 2,530 | A1 | March 29, 2006 (pdf) (181 KB) | Acceptable |
| R-1270 (Propylene) | N | 0 | 1.8 | A3 | December 1, 2016 (pdf) (969 KB) | Unacceptable, as of January 3, 2017. | |
| R-290 (Propane) | N | 0 | 3 | A3 | April 10, 2015 (pdf) (769 KB) | Acceptable with Use Conditions: For use in self-contained room air conditioning; see rule for detailed conditions. | |
| R-404A | SUVA HP-62 | R/N | 0 | 3,920 | A1 | December 20, 2002 (pdf) (168 KB) | Acceptable |
| R-407A | Klea 60, Klea 407A | R/N | 0 | 2,110 | A1 | January 2, 2009 (pdf) (173 KB) | Acceptable |
| R-407C | Suva 407C, Klea 407C | R/N | 0 | 1,770 | A1 | February 8, 1996 (pdf) (152 KB); December 20, 2002 (pdf) (168 KB); August 21, 2003 (pdf) (161 KB) | Acceptable |
| R-407F | Genetron Performax LT | R/N | 0 | 1,820 | A1 | October 4, 2011 (pdf) (201 KB) | Acceptable |
| R-410A | AZ-20, Suva 9100, Puron | N | 0 | 2,090 | A1 | February 8, 1996 (pdf) (152 KB); December 20, 2002 (pdf) (168 KB) | Acceptable |
| R-410B | N | 0 | 2,230 | A1 | February 8, 1996 (pdf) (152 KB) | Acceptable | |
| R-417A | ISCEON 59, NU-22 | R/N | 0 | 2,350 | A1 | December 6, 1999 (pdf) (226 KB); June 16, 2010 (pdf) (229 KB) | Acceptable |
| R-421A | Choice R-421A | R/N | 0 | 2,630 | A1 | September 28, 2006 (pdf) (183 KB) | Acceptable |
| R-422B | ICOR XAC1, NU-22B | R/N | 0 | 2,530 | A1 | March 29, 2006 (pdf) (181 KB) | Acceptable |
| R-422C | ICOR XLT1 | R/N | 0 | 3,390 | A1 | March 29, 2006 (pdf) (181 KB) | Acceptable |
| R-422D | ISCEON MO29 | R/N | 0 | 2,730 | A1 | September 28, 2006 (pdf) (183 KB) | Acceptable |
| R-424A | RS-44 | R/N | 0 | 2,440 | A1 | September 28, 2006 (pdf) (183 KB) | Acceptable |
| R-427A | Forane 427A | R | 0 | 2,140 | A1 | January 2, 2009 (pdf) (173 KB) | Acceptable |
| R-434A | RS-45 | R/N | 0 | 3,250 | A1 | October 4, 2007 (pdf) (163 KB) | Acceptable |
| R-437A | KDD6, ISCEON MO49 Plus | R/N | 0 | 1,810 | A1 | January 2, 2009 (pdf) (173 KB); June 16, 2010 (pdf) (229 KB) | Acceptable |
| R-438A | KDD5, ISCEON MO99 | R/N | 0 | 2,270 | A1 | October 4, 2007 (pdf) (163 KB); June 16, 2010 (pdf) (229 KB) | Acceptable |
| R-441A | N | 0 | <5 | A3 | April 10, 2015 (pdf) (769 KB) | Acceptable with Use Conditions: For use in self-contained room air conditioning; see rule for detailed conditions. | |
| R-443A | N | 0 | 2.5 | A3 | December 1, 2016 (pdf) (969 KB) | Unacceptable, as of January 3, 2017. | |
| R-507, R-507A | AZ-50 | R/N | 0 | 3,990 | A1 | September 5, 1996; December 20, 2002 (pdf) (168 KB) | Acceptable |
| RS-44 (2003 formulation) | R/N | 0 | 2,420 | A1 | June 16, 2010 (pdf) (229 KB) | Acceptable | |
| THR-03 | R/N | 0 | N/A | A1 | December 6, 1999 (pdf) (226 KB) | Acceptable with Use Conditions: For use in residential window unit air conditioning. | |
| R-458A | Bluon TdX 20 | R | 0 | 1,650 | A1 | July 21, 2017 (pdf) (314 KB) | Acceptable |
| R-452B | Opteon™ XL55 | N | 0 | 700 | A2L | May 6, 2021 (pdf) (583 KB) | Acceptable with Use Conditions: See rule for detailed conditions. |
| R-454A | Opteon™ XL40 | N | 0 | 240 | A2L | May 6, 2021 (pdf) (583 KB) | Acceptable with Use Conditions: See rule for detailed conditions. |
| R-454B | Opteon™ XL41 | N | 0 | 470 | A2L | May 6, 2021 (pdf) (583 KB) | Acceptable with Use Conditions: See rule for detailed conditions. |
| R-454C | Opteon™ XL20 | N | 0 | 150 | A2L | May 6, 2021 (pdf) (583 KB) | Acceptable with Use Conditions: See rule for detailed conditions. |
| R-457A | Forane® 457A | N | 0 | 140 | A2L | May 6, 2021 (pdf) (583 KB) | Acceptable with Use Conditions: See rule for detailed conditions. |
| R-513A | Opteon® XP-10 | N | 0 | 630 | A1 | December 11, 2024 (pdf) (300 KB) | Acceptable in self-contained units. |
1 All refrigerants identified as or otherwise meeting the criteria for flammability Class 3 in American National Standards Institute (ANSI)/American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 34–2013 are listed as Unacceptable for use in retrofit unitary split air conditioning systems and heat pumps as of January 3, 2017 (see SNAP Final Rule 21 (pdf) (969 KB) for more details). All refrigerants meeting the criteria for flammability Class 3 include, but are not limited to, R-170 (ethane), R-290 (propane), R-600a (isobutane), R-1270 (propylene), R-441A, R-443A and refrigerant products sold under the names R-22a, 22a, Blue Sky 22a refrigerant, Coolant Express 22a, DURACOOL-22a, EC-22, Ecofreeez EF-22a, Envirosafe 22a, ES-22a, Frost 22a, HC-22a, Maxi-Fridge, MX-22a, Oz-Chill 22a, Priority Cool, and RED TEK 22a.
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