Two refrigerants are replacing R-410A: R-32 and R-454B. As of January 1, 2025, manufacturers can no longer produce new residential and light commercial air conditioning equipment that uses R-410A. Both replacements have significantly lower global warming potential, which is the whole reason for the switch.
Why R-410A Is Being Phased Out
R-410A has a global warming potential (GWP) of 2,088, meaning it traps 2,088 times more heat in the atmosphere than carbon dioxide over a 100-year period. Under the AIM Act, the EPA set new GWP limits for HVAC equipment. Any new split system installed after January 1, 2026, must use a refrigerant with a GWP below 700. R-410A doesn’t come close to meeting that threshold.
The phaseout works in stages. Manufacturing and importing new R-410A residential AC equipment became illegal on January 1, 2025. Equipment that was already built before that date can still be installed through the end of 2025, giving distributors time to clear existing inventory. But starting January 1, 2026, every newly installed system needs to run on a lower-GWP refrigerant. Variable refrigerant flow (VRF) systems get a slightly longer window, with installation of higher-GWP units allowed until January 1, 2027, as long as all components were manufactured before 2026.
R-32: Higher Efficiency, Simpler Chemistry
R-32 is a single-component refrigerant with a GWP of 675. That’s about a third of R-410A’s warming impact. It’s not a new chemical. R-410A itself is actually a 50/50 blend of R-32 and R-125, so R-32 was already doing half the work in your old system.
On its own, R-32 outperforms R-410A. Testing with inverter-driven compressors shows R-32 delivers over 110% of R-410A’s cooling capacity and over 107% of its energy efficiency. In Daikin’s lab testing of rooftop units and water-cooled chillers, R-32 improved full-load and partial-load efficiency by up to 12%. Because it’s a single compound rather than a blend, it’s also easier to reclaim and recycle, and systems need a smaller refrigerant charge to do the same job.
Daikin, Goodman, Mitsubishi Electric, and Gree are the major manufacturers building R-32 equipment. Daikin has been especially aggressive here, having used R-32 in international markets for years before the U.S. transition.
R-454B: The Blend Alternative
R-454B, sold under the brand name Opteon XL41, is a blend of R-32 and R-1234yf. Its GWP is 465, making it the lower-impact option of the two. It performs slightly below R-410A in raw cooling capacity (around 97%) but edges it out in efficiency at over 102%. The differences are small enough that most homeowners won’t notice a change in comfort.
Rheem, Ruud, York, Bosch, and Bard have committed to R-454B for their new product lines. Carrier and Trane, two of the largest names in residential HVAC, have also moved toward R-454B for much of their equipment. Some manufacturers, like Mitsubishi, are using both R-32 and R-454B across different product lines.
How R-32 and R-454B Compare
- Environmental impact: R-454B wins with a GWP of 465 versus R-32’s 675. Both are well under the 700 threshold.
- Cooling capacity: R-32 delivers more than 110% of R-410A’s capacity. R-454B comes in just under R-410A at around 97%.
- Energy efficiency: R-32 leads at over 107% of R-410A’s efficiency. R-454B is slightly above R-410A at over 102%.
- Safety classification: Both are classified as A2L, meaning low toxicity and mildly flammable. R-410A was classified as A1, which means nonflammable. This is the most significant practical change for installation and handling.
What A2L Means for Your Home
R-410A couldn’t catch fire under any normal conditions. Both R-32 and R-454B can, technically, but they burn very slowly. ASHRAE created the 2L subclass specifically for refrigerants like these that have such low burning velocity they’re difficult to ignite in real-world scenarios. You’d need a specific concentration in the air, an ignition source, and poor ventilation all at the same time.
For homeowners, the practical impact is minimal. The equipment itself is designed with leak detection sensors and other safety features to account for the mild flammability. For HVAC technicians, it means updated training, different tools, and new installation codes. You may notice that installation takes slightly longer or that your contractor mentions new safety requirements during the process.
What This Means for Your Current System
If you already have an R-410A system, you don’t need to replace it. The phaseout applies to new equipment, not existing installations. Your current system can be serviced and recharged with R-410A for as long as it keeps running. R-410A refrigerant itself is still being produced and sold for servicing existing equipment.
What you cannot do is retrofit your R-410A system to use R-454B or R-32. Neither is a drop-in replacement. The operating pressures, oil compatibility, and system components are different enough that current codes restrict R-454B and R-32 to equipment specifically designed for them. When your R-410A system eventually reaches the end of its life, your replacement will come with one of the new refrigerants already built in.
The cost of the new equipment is something to keep in mind if you’re planning a replacement in the next year or two. Early-generation products using new refrigerants sometimes carry a premium, and technicians certified to work with A2L refrigerants may charge more during the transition period as the workforce catches up with training requirements. That said, the higher efficiency of R-32 and R-454B systems should translate to lower electricity bills over the life of the unit, offsetting some of the upfront cost.
Which Refrigerant You’ll Get
In most cases, you won’t choose your refrigerant directly. You’ll choose a brand and model, and the refrigerant comes with it. If you prefer Carrier or Trane, you’re likely getting R-454B. If you go with Daikin or Goodman, you’ll probably end up with R-32. Both refrigerants meet federal requirements and both will cool your home effectively. The brand, efficiency rating, and system sizing matter far more to your comfort and energy bills than which of these two refrigerants is inside the unit.