R-454B is the primary replacement for R-410A in the United States. Sold by Carrier under the brand name Puron Advance, R-454B has been adopted by most major HVAC manufacturers and is already shipping in new residential air conditioning and heat pump systems as of 2025. A second option, R-32, is used by Daikin and Goodman. Both refrigerants have a global warming potential (GWP) below 700, which is the new federal limit for residential and light commercial cooling equipment.
Why R-410A Is Being Phased Out
R-410A has a GWP above 2,000, meaning it traps more than 2,000 times as much heat as carbon dioxide over a 100-year period. Under the American Innovation and Manufacturing (AIM) Act, the EPA is phasing down total U.S. production and consumption of hydrofluorocarbons (HFCs) by 85% below historical baseline levels by 2036. The schedule drops in steps: production is capped at 60% of baseline through 2028, then 30% from 2029 to 2033, 20% in 2034 and 2035, and just 15% from 2036 onward.
As part of this phasedown, the EPA set a GWP ceiling of 700 for refrigerants in new residential and light commercial air conditioning and heat pump equipment. Manufacturing and importing new R-410A systems was prohibited starting January 1, 2025. Systems already built before that date can still be installed through January 1, 2026, and the EPA has proposed removing that installation deadline entirely to allow remaining inventory to sell through without a hard cutoff.
R-454B: The Industry’s Leading Choice
R-454B is a blend of R-32 and a small amount of another refrigerant that brings its GWP down to about 466, roughly 78% lower than R-410A. It delivers comparable cooling performance and energy efficiency, so homeowners switching to a new system should not notice a difference in comfort. Carrier, Trane, Lennox, American Standard, and Rheem have all transitioned their 2025 product lines to R-454B, making it the dominant refrigerant across most of the U.S. residential market.
The main technical difference is flammability. R-454B carries an ASHRAE A2L safety classification, meaning it is “mildly flammable.” It requires a high-energy ignition source to catch fire and burns weakly if it does ignite. By comparison, R-410A is classified A1, which means nonflammable. Because of this change, new R-454B systems include built-in safety features like leak detection sensors. Updated building codes in most jurisdictions now account for A2L refrigerants, but local adoption varies.
R-32: The Alternative Path
R-32 is a single-component refrigerant with a GWP of about 675, still well under the 700 threshold. It has excellent heat transfer properties, which can translate to slightly lower energy consumption in some applications. Daikin, the world’s largest HVAC manufacturer, chose R-32 for its residential equipment, and its subsidiary Goodman was the first U.S. manufacturer to adopt R-32 in certain models.
R-32 is also classified A2L, so the same mild-flammability considerations and safety requirements apply. The practical difference for homeowners choosing between a Daikin/Goodman system using R-32 and a Carrier or Trane system using R-454B is minimal. Both meet the new regulations, both perform similarly, and both require the same A2L-rated installation practices. Your choice of refrigerant will largely be determined by which brand and model best fits your home.
What This Means for Existing R-410A Systems
If you already have an R-410A air conditioner or heat pump, it is not affected by the new rules. The phase-out applies to the manufacture and sale of new equipment, not to servicing existing units. You can continue to run, maintain, and recharge your current system with R-410A for as long as the equipment lasts.
That said, R-410A refrigerant will gradually become more expensive. As overall HFC production allowances shrink through 2036, less R-410A will be manufactured each year, and the supply will increasingly come from reclaimed refrigerant recovered from decommissioned systems. For a system that might need a major refrigerant recharge in 2030 or beyond, the cost of that service call could be significantly higher than it is today. This is worth factoring in if you’re deciding between repairing an aging R-410A system and replacing it.
Can You Retrofit an R-410A System?
No. R-454B is not a drop-in replacement for R-410A. You cannot simply swap refrigerants in an existing system. Components like compressors and filter driers must be specifically rated for R-454B, and the required leak-detection safety features are not present in older equipment. The same applies to R-32. When your R-410A system reaches the end of its life, you will need a full system replacement to move to the new refrigerant.
One practical piece of good news: many existing copper linesets (the tubing that connects indoor and outdoor units) may be reusable with a new R-454B system, depending on the manufacturer’s specifications and the condition of the lines. This can reduce installation costs in some cases. Your HVAC contractor can evaluate whether your existing linesets are compatible.
Cost Differences for New Systems
New HVAC systems using R-454B are currently running about 15 to 30% more expensive than the R-410A equipment they replace. That premium reflects both the cost of the refrigerant itself and the added safety components required for A2L compliance, including leak detectors and updated electrical components. As production scales up and the market stabilizes, prices are expected to come down, but the transition period will carry a noticeable cost increase for homeowners buying new systems in 2025 and 2026.
HVAC technicians also need updated equipment for the new refrigerants. While basic hand tools remain the same, vacuum pumps, recovery machines, and leak detectors must be rated for A2L use. If your contractor hasn’t invested in this updated equipment, that’s a red flag worth paying attention to.
Key Dates to Know
- January 1, 2025: Manufacturing and importing new R-410A residential AC and heat pump systems is prohibited. New equipment must use a refrigerant with a GWP below 700.
- January 1, 2026: The original deadline for installing any remaining R-410A inventory, though the EPA has proposed removing this cutoff to allow continued sell-through of pre-2025 stock.
- 2029 to 2033: HFC production drops to 30% of baseline, further tightening R-410A availability for servicing older systems.
- 2036 and beyond: HFC production settles at 15% of baseline, the final step in the phasedown.
For most homeowners, the transition is straightforward. If your current system is working well, there is no urgency to replace it. When the time comes for a new system, R-454B or R-32 equipment will be the standard option available from every major manufacturer.