Last reviewed: August 2026 · By the HVAC Brief Editorial Team · Our sourcing and editorial standards
Twenty months into the A2L transition, the manufacturing side is settled and the service side is not. New residential equipment moved to R-454B and similar blends on January 1, 2025. The installed base is still overwhelmingly R-410A, and will be for years.
What changed most recently is the installation rule: EPA removed the cutoff on pre-2025 inventory effective July 27, 2026, so both refrigerants are being installed simultaneously.
Where each piece stands
| Element | Status |
|---|---|
| New residential equipment manufacture | Must be under 700 GWP since January 1, 2025 |
| Installing pre-2025 R-410A inventory | Permitted federally, no end date, since July 27, 2026 |
| Servicing existing R-410A systems | Legal, using produced or reclaimed refrigerant |
| EPA 608 certification | Unchanged. No A2L-specific federal certification exists |
| Refrigerant supply | Capped at 60% of baseline, dropping to 30% in 2029 |
| Trade measures on imported refrigerant | Antidumping orders on HFC blends and R-32 maintained in 2026 |
The gap nobody legislated
EPA Section 608 requirements did not change when the refrigerants did. A technician certified in 2015 holds a valid certification that says nothing about A2L handling, storage or tooling. The regulatory framework treats certification as current while the field material has changed underneath it.
That is not a compliance failure, it is a training gap, and it sits with employers rather than with the certification scheme. See what 608 actually covers and what A2L changes in practice.
Because pre-2025 inventory remains installable with no federal end date, a contractor can be installing R-454B on Monday and R-410A on Tuesday. That means A2L-rated tooling and recovery equipment alongside the existing kit, not instead of it, for as long as the inventory lasts.
Frequently asked questions
Where does the A2L transition stand in 2026?
New residential equipment has been under the 700 GWP limit since January 1, 2025, so it ships with R-454B or similar. Pre-2025 R-410A inventory remains installable federally with no end date after an EPA rule effective July 27, 2026. The installed base is still overwhelmingly R-410A.
Do technicians need new certification for A2L?
No federal A2L-specific certification exists. EPA Section 608 requirements were unchanged by the transition, so an existing certification remains valid. The gap is training rather than certification, and it sits with employers.
Can contractors install both R-410A and R-454B equipment?
Yes. Pre-2025 R-410A inventory remains installable federally with no end date, while new equipment ships with A2L refrigerant. That means carrying A2L-rated tooling and recovery equipment alongside existing kit rather than replacing it.
Sources
- 40 CFR 84.54 and EPA final rule 91 FR 31284, effective July 27, 2026; 40 CFR 84.7 phasedown schedule.
- 40 CFR 82.161, technician certification.
- US Department of Commerce, 91 FR 48079 and 91 FR 51658, antidumping proceedings.
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