Research
The refrigerant change nobody told homeowners about
What changed on January 1, 2025, what did not, and the 2026 deadline most articles still repeat that no longer exists.
Written by HYRE HVAC Research Desk Primary-source research, data analysis and fact checking
The finding
Since January 1, 2025, new US home air conditioners and heat pumps must use a refrigerant with a global warming potential (GWP) of 700 or less. That rules out R-410A, at GWP 2,088.
The January 1, 2026 deadline to install older R-410A stock no longer exists: EPA’s final rule of May 21, 2026 removed it. No rule requires you to replace a working R-410A system.
What changed on January 1, 2025?
The American Innovation and Manufacturing Act directs EPA to phase down hydrofluorocarbons, and its Technology Transitions program does so sector by sector. For residential and light commercial air conditioning and heat pumps, the rule sets a global warming potential limit of 700, effective for manufacture and import from January 1, 2025.
R-410A was the standard home refrigerant for two decades. Its GWP of 2,088 is roughly three times the limit, so it is out for new equipment. Two refrigerants have replaced it: R-32 at GWP 675 and R-454B at GWP 465. Technicians who handle any of them need EPA Section 608 certification.
HyreHVAC analysis: the most widely published GWP for R-454B is wrong, and we published it wrong ourselves. The figure in general circulation is 698, which would put R-454B barely under the 700 limit.
On EPA’s own reference table, 698 is the row for R-452B, a different blend. R-454B reads 465. The two rows sit close together and the names differ by one character.
You can check the correct value by hand. R-454B is 68.9% R-32 / 31.1% R-1234yf by weight. R-1234yf’s GWP is below 1, and 0.689 x 675 is 465. So R-454B is not squeezed in just under the limit.
It clears it by 235 points, and R-32 clears it by 25. GWP headroom is not what decided between them. If a comparison puts R-454B in the high six hundreds, it copied the adjacent row.
One note on the numbers. The AIM Act uses the 100-year GWPs from Table 2.14 of the IPCC’s Fourth Assessment Report, published in 2007. Newer assessments give different values, and EPA’s greenhouse gas equivalencies calculator uses the newer ones. The regulation does not. Figures quoted elsewhere may differ for that reason alone.
Is there still a January 1, 2026 installation deadline?
No. The 2023 final rule allowed R-410A equipment built or imported before January 1, 2025 to be installed until January 1, 2026. That date was reported everywhere, drove a lot of buying through 2025, and much of the advice written then is still online.
It is gone, and much coverage credits the wrong document for removing it. EPA proposed the change in September 2025 and announced enforcement discretion at the same time.
A proposal does not remove a rule. EPA’s final rule of May 21, 2026 did (91 FR 31284, published May 26, 2026, effective July 27, 2026).
EPA’s current HFC Restrictions by Sector table now states: "No installation compliance date for residential and light commercial systems where all specified components were manufactured or imported before January 1, 2025."
If you are reading advice that tells you to buy before an installation deadline, check its date. There is no such deadline for residential systems today.
Variable refrigerant flow (VRF) systems are a different subsector and still carry one: January 1, 2027, extended to January 1, 2028 for buildings with permits approved before October 5, 2023.
Which refrigerant do new heat pumps use now?
Mostly R-454B. Rule dates say what is allowed; what manufacturers did is a separate question. ENERGY STAR records the refrigerant of every certified model, so it can be measured. It is the same database behind our cold-climate heat pump study. Across 12,562 distinct certified outdoor units:
R-454B is now the most common refrigerant in the catalog at 47.8% (6,007 units), followed by R-410A at 35.3% (4,429) and R-32 at 16.9% (2,126).
HyreHVAC analysis: the R-410A share is the interesting number, and it needs care. Roughly a third of the certified catalog still lists a refrigerant that cannot go into newly built equipment. That is not evidence of breaking the rule.
Certification records stay after a model leaves production, and this is a catalog, not a count of shipments. It does show the change is recent: the old R-410A catalog is still larger than the R-32 one, and a buyer browsing model listings will see both.
What does the rule say, in one table?
| Question | Answer |
|---|---|
| GWP limit, residential AC and heat pumps | 700 |
| In force for manufacture and import from | January 1, 2025 |
| Installation deadline for pre-2025 R-410A stock | None: The January 1, 2026 date was removed |
| Do I have to replace a working R-410A system? | No. No rule requires replacement of installed equipment |
| Can my R-410A system still be serviced? | Yes. R-410A remains legal to produce, sell and use for servicing |
| Variable refrigerant flow installation deadline | January 1, 2027 |
| VRF extended deadline | January 1, 2028 for buildings with permits approved before October 5, 2023 |
| R-410A GWP | 2,088 |
| R-32 GWP | 675 |
| R-454B GWP | 465 |
| Which IPCC values the rule uses | Fourth Assessment Report (2007), Table 2.14 |
Provisions of EPA’s Technology Transitions program for the residential and light commercial air conditioning and heat pump subsector, as published on EPA’s own sector table and checked September 5, 2026.
This subsector has been reconsidered once already. Re-check EPA’s sector table before relying on any of it for a purchasing decision.
What does it mean if you own an R-410A system?
No provision of this rule requires anyone to remove or replace installed equipment. Any sales approach that says otherwise is misrepresenting the regulation.
R-410A remains legal to produce, sell and use for servicing existing systems. The restriction is on what may be manufactured, not on what may be repaired.
The AIM Act phases down HFC production on a schedule, so the supply of R-410A tightens over the coming years even though servicing remains legal.
It is a reason to weigh a large repair on an old system carefully, using a tool like the repair or replace calculator. It is not a reason to replace a working one now.
R-32 and R-454B carry ASHRAE safety classification A2L, against A1 for R-410A. That changes leak detection requirements, charge limits and service practice, and it is why technicians have needed retraining. It is a handling matter, not a hazard to occupants of a correctly installed system.
A system is designed for one refrigerant. Retrofitting an R-410A system to R-454B is not a supported operation, and a quote that proposes it should be questioned. If your system is leaking now, see refrigerant leak detection and repair.
The single most common piece of outdated advice on this subject is that pre-2025 stock must be installed by January 1, 2026. It must not. If a quote is urgent for that reason, the reason is wrong.
How did we check this, and what are the limits?
Every date and threshold on this page was read from EPA’s own pages on September 5, 2026, not from secondary coverage: the HFC Restrictions by Sector table for the compliance dates, and the Technology Transitions GWP Reference Table for the GWP values. The URLs are in the sources below.
From the ENERGY STAR certified product database, September 4, 2026. Computed over 12,562 distinct outdoor units rather than certified combinations, because a single outdoor unit appears once per indoor pairing and counting rows would distort the shares.
The refrigerant shares describe the certified catalog, weighting every model equally regardless of sales volume. Certification records also persist after a model leaves production, which is why R-410A still appears at a substantial share. No public dataset gives shipment-weighted refrigerant shares.
The residential subsector has been through one full reconsideration, proposed in September 2025 and finalized on May 21, 2026 (91 FR 31284, effective July 27, 2026), which removed a deadline this page would previously have reported as binding.
As of September 5, 2026 that reconsideration is final and no further proposal affecting this subsector is open. That is a statement about a moving target: anything here could change again, and the sources are linked so you can check rather than trust.
Until September 5, 2026 this page gave R-454B a GWP of 698 and built an analysis paragraph on the two points of headroom that implied.
698 is EPA’s value for R-452B, a different blend. The correct figure is 465, the analysis has been rewritten rather than patched, and we are leaving this note here rather than removing the trace.
This describes a federal rule as published. State and local codes impose their own requirements on A2L refrigerants, particularly around charge limits and ventilation, and those are not covered here.
Questions
Is R-410A banned?
Do I have to install my R-410A unit before January 2026?
What replaced R-410A?
Will my existing air conditioner still be serviceable?
Are the new refrigerants flammable?
Can my R-410A system be converted to the new refrigerant?
Written and audited by
HYRE HVAC Research Desk
Primary-source research, data analysis and fact checking
We are a research desk, not a sales floor. We read the federal microdata file, the statute or the manufacturer data sheet ourselves, and we publish the figure with the document it came from and the date we retrieved it.
Where a number cannot be traced to a primary source, we publish the shorter page and say what we could not verify.
The counts below are generated from the published pages themselves, last counted September 28, 2026, and they are what we have actually published rather than what we intend to.
- 13
- studies published
- 12
- federal sources read and cited
- 8
- studies published with their full dataset as CSV
- 51
- jurisdictions reproduced against EIA’s own tables
How this desk works
- Primary sources only. Federal data comes from the agency that collects it, in the file that agency publishes. We do not cite an article that cites a source; we download the source and compute the figure ourselves.
- We validate against the agency before we publish. First, we use each federal microdata file to reproduce the agency’s own published tables. Our cooling research reproduces EIA’s state estimates and standard errors for all 51 jurisdictions. That check caught a variance formula that was off by a factor of four.
- Every estimate carries its uncertainty. These are survey figures, not counts. Standard errors are computed from the replicate weights the federal file supplies and printed beside the estimate. An estimate too imprecise to publish is reported as such rather than printed.
- Nothing is typed by hand. Prose, tables and charts all read from one dataset built by script, so a number in a sentence and the same number in the table below it cannot disagree.
- We publish the data, not just the conclusion. 8 of our 13 studies offer the full computed table as a CSV download on the page, so you can check the analysis or disagree with it. A study without a row-level dataset gets no download link and claims none in its structured data.
- We correct in public. Where we have published a figure wrongly we fix the figure, rewrite any analysis that rested on it rather than patching the number underneath it, and leave a dated correction note on the page.
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Data as of EPA rule provisions checked September 5, 2026; ENERGY STAR catalog September 4, 2026. Authorship on this site is organizational: the analysis belongs to the desk rather than to a named individual, and we do not publish credentials we do not hold.
Our editorial policy sets out how we source, date and correct what we publish.
Sources & retrieval dates
Repair it or replace it?
Refrigerant supply is one input into that decision and rarely the deciding one. The calculator weighs it against remaining life and the cost of the repair in front of you.