R-410A after 2025: EPA rules for home AC and heat pumps

Status on the date checked

EPA limit for new home AC and heat pump systems (R-410A)

New systems need a refrigerant below GWP 700, except systems built entirely from components made or imported before January 1, 2025, which have no install deadline since July 27, 2026 (91 FR 31284).

New York, 6 NYCRR Part 494

New field-charged home AC and heat pump systems with these refrigerants prohibited after January 1, 2026; above a GWP20 of 10, after January 1, 2034.

On October 13, 2026, no federal rule stops you from using or repairing an air conditioner or heat pump that runs on R-410A. EPA’s Technology Transitions rule limits the installation of new systems. Since January 1, 2025, a new residential or light commercial AC or heat pump system may not be installed with an HFC refrigerant that has a global warming potential (GWP) of 700 or more (40 CFR 84.54(c)(1)). R-410A has a GWP of 2,088 (EPA, Technology Transitions GWP Reference Table). EPA notes that U.S. manufacturers already supply equipment using R-32 or R-454B, both below 700 91 FR 31284, p. 31321.

In EPA’s documents the change away from R-410A has two separate parts: the Technology Transitions rule, which limits new systems, and the HFC phasedown, which steps down HFC production and consumption over time 88 FR 73098, pp. 73139–73140. Neither bans using an existing system: EPA says there are “no requirements to stop using any specific equipment or appliance currently in use” (EPA FAQ).

One exception remains, and EPA changed it in 2026. A new system may still be installed with R-410A equipment if every specified component of the system was made in, or imported into, the United States before January 1, 2025. Until July 26, 2026 that was allowed only for installations before January 1, 2026. EPA’s amendment, published May 26, 2026 and effective July 27, 2026, removed the deadline (91 FR 31284; 40 CFR 84.54(c)(1)).

New York’s own rule, 6 NYCRR Part 494, still lists January 1, 2026 as the prohibition date for these new systems, and DEC says federal changes are not adopted automatically. See the New York section below.

What the federal rule restricts

The restriction comes from EPA’s 2023 Technology Transitions rule (88 FR 73098, published October 24, 2023, effective December 26, 2023), issued under the American Innovation and Manufacturing (AIM) Act of 2020. The AIM Act was enacted December 27, 2020 (EPA, Background on HFCs and the AIM Act). For residential and light commercial AC and heat pump systems other than variable refrigerant flow (VRF) systems, the restriction applies from January 1, 2025 88 FR 73098, p. 73208.

What it restricts is installing. In the regulation, install means “to complete a field-assembled system’s circuit, including charging with a full charge, such that the system can function and is ready for use for its intended purpose” (40 CFR 84.52). A system is “an assemblage of separate components that typically are connected and charged in the field”, and the specified components are condensing units, condensers, compressors, evaporator units and evaporators (40 CFR 84.52). EPA’s 2026 rule describes the systems in this subsector as “unitary split systems such as ducted and non-ducted mini-splits, multi-splits, and ducted air conditioners and heat pumps” 91 FR 31284, p. 31300.

Once the system is charged to full charge, these jobs count as installing a new system (40 CFR 84.54(e)):

• assembling a system for the first time from used or new components;
• increasing the cooling capacity, in Btu per hour, of an existing system (for supermarket systems, by more than 15 percent);
• replacing 75 percent or more of the evaporators (by number) and all of the compressor racks, condensers and connected evaporator loads of an existing system.

For a home split system, EPA’s FAQ puts it more simply: a new system is one installed in a newly built home, or one where the condensing unit and the indoor coil are replaced together. The condensing unit contains the condenser coil and compressor; the indoor coil is the evaporator (EPA, Frequent Questions on the Phasedown of Hydrofluorocarbons). Replacing only the condensing unit on an existing system “is allowed and is not considered the installation of a new system” 91 FR 31284, p. 31322.

Replacing the two parts at different times is treated differently in two EPA documents. The 2026 rule says: “The EPA has consistently stated that replacing all components over time constitutes the installation of a new system.” Under that approach, replacing the condensing unit without the indoor coil is not a new system, but “the subsequent replacement of the indoor coil would be considered the installation of a new system which cannot use a refrigerant that exceeds the limit”, and the same applies if the coil is replaced first and the condensing unit later 91 FR 31284, p. 31318. EPA’s FAQ, updated September 14, 2026, answers the question “Can I replace the condensing unit and replace the indoor coil at a later time?” with “Yes. Systems may be repaired over time.” This page follows the Federal Register text. By our reading of 40 CFR 84.54(c)(1), a system that becomes new this way could still use R-410A only if all of its specified components were made in or imported into the U.S. before January 1, 2025.

What changed in 2026

Date	Action	Document
December 26, 2023	Interim final rule: new systems built from components made or imported before January 1, 2025 may be installed before January 1, 2026	88 FR 88825
October 3, 2025	EPA proposes letting that equipment be installed with no deadline; the comment period is later extended to November 21, 2025	90 FR 47999; 90 FR 51042
May 26, 2026	Final rule published	91 FR 31284
July 27, 2026	Final rule takes effect	91 FR 31284

EPA’s fact sheet says the agency finalized the rule on May 21, 2026 EPA Technical Fact Sheet, p. 1. The Federal Register copy shows it filed on May 22 and published on May 26 91 FR 31284, p. 31330.

The amendment deleted “prior to January 1, 2026” from 40 CFR 84.54(c)(1). The text in force on July 26, 2026 said such systems “may be installed prior to January 1, 2026, where all specified components of that system are manufactured or imported prior to January 1, 2025.” The current text says they “may continue to be installed where all specified components of that system are manufactured or imported prior to January 1, 2025” (40 CFR 84.54(c)(1), eCFR as of October 8, 2026). EPA also considered moving the deadline to January 1, 2027 and chose to remove it instead. It wrote that installing the remaining R-410A inventory “could be a lower cost option for consumers” 91 FR 31284, p. 31300.

The exception depends on where and when the equipment was made. Equipment manufactured in Mexico or Canada before January 1, 2025 and imported into the United States after that date “may not be installed as components of a new system” 91 FR 31284, p. 31322. EPA describes the stock as “a finite and decreasing inventory of equipment” and “acknowledges a lack of concrete data on the number of R-410A units that remain in inventory” 91 FR 31284, p. 31322.

What did not change

The GWP limit of 700 and the January 1, 2025 start date stay. In EPA’s words: “Installing new R-410A systems using equipment domestically manufactured or imported after January 1, 2025, remains prohibited” 91 FR 31284, p. 31322.

Repairs are treated as before. EPA made no change to the definitions, the list of actions that count as a new system, the exemption for components or the treatment of replacement condensing units, so that “a homeowner can choose to replace their failed condensing unit rather than purchase a whole new system” 91 FR 31284, p. 31297. The bans on making, importing and selling products do not apply to components (40 CFR 84.56(b)). An R-410A specified component made or imported from January 1, 2025 on must carry a permanent label that reads “For servicing existing equipment only” (40 CFR 84.58(b)).

VRF systems keep their own dates, which the 2026 rule did not extend. New VRF systems using a refrigerant with a GWP of 700 or more may be installed before January 1, 2027 if all specified components were made or imported before January 1, 2026 (40 CFR 84.54(c)(2)). EPA also describes an earlier delay “until January 1, 2028, for certain projects that received an approved building permit before October 5, 2023” 91 FR 31284, p. 31322.

Window units and portable room air conditioners are regulated as self-contained products. Making or importing them with a refrigerant GWP of 700 or more has been prohibited since January 1, 2025 (40 CFR 84.54(a)(1)). Selling, distributing and exporting them is prohibited three years after that date (40 CFR 84.54(b); EPA, Technology Transitions HFC Restrictions by Sector), which by our arithmetic is January 1, 2028.

R-32, R-454B and the A2L safety class

R-32 (HFC-32) and R-454B are in safety group A2L under ANSI/ASHRAE Standard 34-2019 88 FR 26382, p. 26387. The letter in the code indicates toxicity and the numeral indicates flammability 88 FR 26382, p. 26386. EPA describes HFC-32’s A2L class as “low toxicity and lower flammability” 88 FR 26382, p. 26395. A refrigerant gets the 2L class if, when tested, it shows flame propagation but has a heat of combustion below 8,169 Btu/lb (19,000 kJ/kg) and a maximum burning velocity of 10 cm/s (about 3.9 in/s) or lower, among other limits 88 FR 26382, p. 26386.

EPA states that A2L refrigerants “require a higher amount of energy to ignite than A3 refrigerants”, and it agreed with a commenter that static electricity, a spark from a closing door or a cigarette are not considered sufficient ignition sources for HFC-32 88 FR 26382, p. 26399. It also wrote that the flammability risks “are of potential concern because residential ACs and HPs traditionally used refrigerants that are not flammable” 88 FR 26382, p. 26395.

EPA’s Significant New Alternatives Policy (SNAP) program lists R-32 and R-454B as “Acceptable with Use Conditions” for residential and light commercial AC and heat pumps (EPA SNAP page, updated March 19, 2026). The conditions are set in the SNAP rules; this page does not summarize them.

Refrigerant	ASHRAE 34 safety group	GWP (EPA Technology Transitions table)	SNAP status, residential AC and heat pumps
R-410A	A1	2,088	Acceptable
R-32 (HFC-32)	A2L	675	Acceptable with Use Conditions
R-454B	A2L	465	Acceptable with Use Conditions

R-454B is a blend of 68.9 percent HFC-32 and 31.1 percent HFO-1234yf 88 FR 26382, p. 26387. GWP values differ slightly between EPA documents. The table uses EPA’s Technology Transitions GWP Reference Table (updated April 2, 2026), the set of values used for this rule; the SNAP rule gives about 2,090 for R-410A and about 470 for R-454B 88 FR 26382, p. 26395. By either set of figures, R-32 and R-454B are below 700 and R-410A is well above it.

Refrigerant work and EPA Section 608

EPA requires technicians “who maintain, service, repair, or dispose of equipment that could release refrigerants into the atmosphere” to be certified under Section 608 of the Clean Air Act (EPA, Section 608 Technician Certification Requirements). The certification rule covers any person who could reasonably be expected to violate the integrity of the refrigerant circuit, and since January 1, 2018 it has applied to appliances with non-exempt substitute refrigerants as well (40 CFR 82.161). R-410A, R-32 and R-454B are not on the list of exempt substitutes in 40 CFR 82.154(a)(1) (our reading of the list). Sales of these refrigerants are restricted too: the conditions in 40 CFR 82.154(c)(1) include the buyer being a certified technician, or employing one and giving the seller proof.

By our reading of 40 CFR 82.161(a)(1), any job that opens the refrigerant circuit, such as adding refrigerant or replacing a compressor or condensing unit, is work for a Section 608 certified technician.

New York: 6 NYCRR Part 494

New York regulates HFCs in 6 NYCRR Part 494, administered by the Department of Environmental Conservation (DEC). The amended rule took effect January 9, 2025 DEC FAQ, p. 4. For residential and light commercial AC and heat pumps, its table lists two prohibition dates (6 NYCRR 494-1.4(e)(2)(v)):

Prohibited substances	Prohibition date
Regulated substances under 40 CFR 84.54(a)(1) and 84.54(c)(1)	January 1, 2026
Regulated substances with a GWP20 greater than 10	January 1, 2034

No person may install a field-charged system in New York that uses a prohibited substance after the prohibition date (494-1.4(a)). Part 494 incorporates 40 CFR 84.54 as effective December 26, 2023 (494-1.11). DEC’s FAQ says “changes to federal regulations are not automatically incorporated into Part 494. The same applies to extensions, no action assurances, or other decisions made by EPA” DEC FAQ, p. 4. On the earlier one-year federal extension for AC systems, the FAQ says Part 494 “adopted the later date”, January 1, 2026 DEC FAQ, p. 7. The DEC documents we read do not name EPA’s 2026 rule. By our reading of 494-1.11 and DEC’s general statement, EPA’s 2026 removal of the deadline is not part of Part 494, so the January 1, 2026 date still applies in New York to new systems built from pre-2025 R-410A equipment.

The 2034 limit uses GWP20, the global warming potential over 20 years. DEC’s FAQ lists R-32 and R-454B among refrigerants with a GWP20 above 1,600 DEC FAQ, p. 8, so by DEC’s figures both are above the 2034 limit of 10.

Part 494 applies to any person who sells, imports, manufactures or distributes covered products in New York, or “installs by a commercial entity or person”, among others (494-1.2(a)). DEC’s factsheet says: “Residential users and consumers are not regulated under Part 494” DEC Factsheet, p. 2.

Nothing in Part 494 requires someone who acquired equipment before the prohibition date to stop using it (494-1.2(c)). DEC’s FAQ lists “using, servicing, renting, leasing, or transferring ownership of any system that was legally installed” as not prohibited DEC FAQ, p. 6. The same FAQ warns that you may “trigger” the definition of new “when retrofitting equipment (changing the refrigerant), increasing system capacity, or replacing components” DEC FAQ, p. 6.

Where an approved building permit issued before January 9, 2025 specifies the refrigerant, the prohibition date is extended one year (494-1.5(a)(12); DEC FAQ, p. 8). DEC’s enforcement discretion letter of June 29, 2026 extends the date to January 1, 2028 for certain VRF and remote condensing unit systems whose installation was held up by construction delays beyond the installer’s reasonable control DEC letter, June 29, 2026, p. 1. Among the letters DEC listed as in effect on its Climate Change Regulatory Revisions page on October 13, 2026, we found none for residential AC or heat pumps.

Part 494 also sets prohibition dates for bulk containers of virgin refrigerant: January 1, 2030 for refrigerants with a GWP100 above 1,500, with R-410A as DEC’s example, and January 1, 2040 for those with a GWP20 of 1,600 or more, where DEC names R-32 and R-454B (494-1.4(f); DEC FAQ, p. 8). DEC says “the prohibition on containers does not apply to the servicing of equipment and there is no prohibition on the sale of repair services that may require the use of these substances” DEC FAQ, p. 9.

Lawsuits

Besides home AC and heat pumps, the 2026 rule changed restrictions in commercial refrigeration subsectors, including cold storage warehouses, remote condensing units and supermarket systems (EPA, Regulatory Actions for Technology Transitions). Petitions for judicial review had to be filed in the U.S. Court of Appeals for the D.C. Circuit by July 27, 2026 91 FR 31284, p. 31289. EPA’s list, updated August 13, 2026, shows five, all marked “Active Litigation”:

Petitioners	Case No.	Filed	What the petition challenges
HARDI, PHCC and ACCA	26-1168	June 24, 2026	Only the changes for cold storage warehouses, remote condensing units and supermarket systems (84.54(c)(9), (c)(11), (c)(12))
AHRI and Alliance for Responsible Atmospheric Policy	26-1174	June 25, 2026	Only the changes for remote condensing units and supermarket systems, and the 60-day effective date for those changes
Natural Resources Defense Council	26-1188	July 20, 2026	The final action; the petition names no narrower part
Commonwealth of Massachusetts et al.	Not printed	July 21, 2026	The final action; the petition names no narrower part
ALTA Refrigeration and CUSER	26-1202	July 24, 2026	Only cold storage warehouse systems (84.54(c)(9)(ii))

By their own text, three of the petitions are limited to commercial refrigeration provisions, and none of those three concerns residential AC or heat pumps. The NRDC and state petitions do not say which parts of the rule they contest. EPA wrote that it “intends that each change to restrictions in distinct applications be severable from all other changes to restrictions in distinct applications” 91 FR 31284, p. 31288.

For the 2023 rule, EPA’s list shows two petitions (Nos. 23-1344 and 23-1345) dismissed on June 24, 2026 and one (No. 23-1347) in abeyance.

What this means for you

• If your R-410A system works, the federal rule does not require you to replace it. EPA says the 2023 rule “does not limit the use of any existing product or system” and was designed so owners “can continue to use and repair legacy systems throughout their useful life” (EPA FAQ).
• If a part fails, EPA’s FAQ says it can be replaced with a similar R-410A part, including the condensing unit or the indoor coil. Replacing the condensing unit alone does not create a new system 91 FR 31284, p. 31322. If you replace the outdoor unit now and the indoor coil later, or the other way round, EPA’s 2026 rule treats the second replacement as installing a new system 91 FR 31284, p. 31318, even though the FAQ says systems “may be repaired over time”. Plan the second replacement with that in mind. EPA adds that “the availability of HFCs and components may lessen over time as HFCs are phased down” (EPA FAQ).
• Replacing the condensing unit and indoor coil together, or putting a system in a new home, is a new system. Under the federal rule it needs a refrigerant below GWP 700, or R-410A equipment whose specified components were all made in or imported into the U.S. before January 1, 2025. R-410A components made or imported from that date on carry the “For servicing existing equipment only” label (40 CFR 84.58(b)) and cannot go into a new system. Ask the installer for the manufacture dates of the condensing unit and coil.
• Under the AIM Act phasedown, HFC production and consumption step down on January 1 of 2029, 2034 and 2036. From 2029 they fall to 30 percent of the baseline, and from 2036 they continue at 15 percent 88 FR 73098, pp. 73139–73140. EPA “recognizes that the price of refrigerant using legacy HFCs may rise as the phasedown continues” 91 FR 31284, p. 31318.
• The requirement to service equipment with reclaimed HFCs from January 1, 2029 lists supermarket systems, refrigerated transport and automatic commercial ice makers. Home AC and heat pumps are not on that list (EPA FAQ).
• On R-454B supply, EPA’s 2026 rule describes “supply chain issues observed in 2025”: there was sufficient R-454B overall, but getting it to contractors and technicians in service cylinders was a challenge, “resulting in R-454B scarcity in some regions” 91 FR 31284, p. 31300.
• In New York, Part 494 lists January 1, 2026 as the prohibition date for new systems with these refrigerants, apart from the building permit extension. By our reading, pre-2025 R-410A equipment therefore cannot be installed there as a new system; DEC has not said so about EPA’s 2026 rule in the documents we read.
• By our reading of 40 CFR 82.161(a)(1), adding refrigerant, recovering it or replacing any part of the sealed circuit is work for a technician certified under EPA Section 608.

What we could not confirm

• Installations of pre-2025 R-410A systems between January 1 and July 26, 2026. The text in force during that period allowed them only before January 1, 2026. The 2026 rule does not address installations made in that window, and the documents we read contain no EPA no-action assurance for home AC and heat pumps.
• How much pre-2025 R-410A equipment is left. EPA says it lacks the data. We found no primary source for the figures that circulate on the share of A2L equipment in sales; EPA’s rule cites only a trade association press release 91 FR 31284, p. 31300, footnote 108.
• EPA’s FAQ, updated September 14, 2026, still says “Any new split system installed after January 1, 2026, must use refrigerant with a GWP less than 700.” That conflicts with the amended regulation and with EPA’s own HFC Restrictions by Sector page (updated August 28, 2026), which shows “No installation compliance date” for systems whose specified components were all made or imported before January 1, 2025. This page follows the Federal Register and eCFR.
• Replacing the condensing unit and the indoor coil at different times. EPA’s 2026 rule calls the second replacement the installation of a new system 91 FR 31284, p. 31318; EPA’s FAQ (updated September 14, 2026) says “Systems may be repaired over time.” We found no EPA document that reconciles the two, and we do not know which reading EPA applies in enforcement.
• New York and EPA’s 2026 rule. None of the DEC documents we read (the FAQ updated October 2026, the factsheet, the enforcement discretion letters, DEC’s Part 494 page) names EPA’s 2026 rule. Our conclusion that the pre-2025 R-410A exception does not apply in New York rests on 494-1.11 and DEC’s general statement that federal changes are not adopted automatically.
• The SNAP use conditions for R-32 and R-454B. We have not read them.
• Court records. We did not obtain the D.C. Circuit dockets, so we do not know what has happened in these cases since August 13, 2026. The Massachusetts petition’s case number is not printed on EPA’s list or on the petition.
• The official New York text. We used DEC’s copy of the Part 494 Express Terms, not the Department of State’s NYCRR compilation. The Express Terms do not print the effective date; January 9, 2025 comes from DEC’s FAQ. We also did not find which component replacements count as new under Part 494. A New York owner replacing only the outdoor unit should ask the installer how Part 494 applies.
• Rules in other states. This page covers federal rules and New York only.
• The date EPA’s Administrator signed the 2026 rule. It is not printed in the Federal Register document.

See also

• Heat pump vs gas calculator
• HVAC and furnace tax credits in 2025 and 2026: 25C, 25D, 30C

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