R-410A to A2L: what the refrigerant change means for your system
Manufacture and import of new residential split systems using refrigerants above 700 GWP — R-410A is about 2,088 — was prohibited from 1 January 2025 under the EPA's Technology Transitions rule. An EPA final rule effective 27 July 2026 lets R-410A equipment built before that date keep being installed until supplies run out. Existing systems stay legal and repairable.
What actually changed, and when
AIM Act, EPA Technology TransitionsUnder the AIM Act of 2020, the EPA's Technology Transitions rule prohibited the manufacture and import of new residential split-system air conditioners and heat pumps using refrigerants above 700 GWP from 1 January 2025. R-410A sits at roughly 2,088 GWP, so it is in scope. New residential equipment now ships with R-454B (GWP about 466) or R-32 (about 675).
Both are classified A2L: mildly flammable. That is not a reason to avoid them — it is the reason service practices, leak detection and technician training changed with them.
The EPA then issued a final rule effective 27 July 2026 allowing continued installation of R-410A units manufactured or imported before 1 January 2025 until existing supplies are depleted. The earlier plan had cut installation off on 1 January 2026.
EPA Technology Transitions rule under the AIM Act of 2020.
What it means for a house in this city
Seminole County Property AppraiserTake the median: a residential parcel in Altamonte Springs built in 1981, 45 years old. It is on its second or third system. Whatever went in most recently is almost certainly R-410A.
Nothing about that system is now illegal. You may keep it, service it and repair it. What has changed is the supply of matched replacement parts: as the pre-2025 stock is drawn down, a failed coil or compressor increasingly pushes toward a full changeout rather than a partial repair, because a matched R-410A replacement may simply not be available in the size you need.
And 8.2% of parcels here predate 1970. A handful of those may still be on R-22, which is repairable only with reclaimed refrigerant. That is not a repair-or-replace decision so much as a countdown.
Seminole County Property Appraiser CAMA extract (Parcels.csv, 5 September 2026), tax district A1 — Altamonte Springs. 13,253 improved residential parcels: single-family, townhome and condominium. Apartments and manufactured homes excluded.
Questions worth asking a contractor right now
Four- Is the quote R-410A or A2L? Both can be legitimate in 2026. You are entitled to know which, because it affects how long parts stay available.
- Is the technician trained and equipped for A2L? Different handling, different leak detection, different recovery equipment.
- Is the system matched? A new condenser on an old indoor coil is neither the rated efficiency nor a warrantable installation.
- Does it meet the rebate threshold? Refrigerant and efficiency are separate questions. Code minimum is below every Duke tier.
Related questions
FAQWhat is the R-410A phase-out timeline?
Manufacture and import of new residential split systems using refrigerants above 700 GWP — R-410A is about 2,088 — was prohibited from 1 January 2025 under the EPA's Technology Transitions rule. An EPA final rule effective 27 July 2026 lets R-410A equipment built before that date keep being installed until supplies run out. Existing systems stay legal and repairable.