HVAC Refrigerants Explained: R-22, R-410A, and the 2025 Switch to R-454B

Your air conditioner doesn't actually produce "cold" — it moves heat from inside your home to the outside. The substance that makes that heat transfer possible is refrigerant, and the refrigerant in residential HVAC systems has changed dramatically in the past decade.

If you're dealing with an AC leak, facing a repair quote, or shopping for a new system, understanding these three refrigerants will help you make a better decision — and ask better questions of your contractor.

Why refrigerants keep changing: the regulatory backstory

The EPA regulates refrigerants because they affect both the ozone layer and the climate. Here's the simplified timeline:

1990s–2009: R-22 era. Chlorodifluoromethane (HCFC-22), sold as Freon, was the standard residential AC refrigerant. It's highly effective, but it damages the ozone layer. The US phased in import and production restrictions beginning in the early 2000s, with a full ban on R-22 production and import taking effect January 1, 2020 under the EPA's HCFC phaseout program, part of the Montreal Protocol commitments.

2010–2024: R-410A era. R-410A (marketed as Puron by Carrier and others) replaced R-22. It doesn't harm the ozone layer — but it has a very high global warming potential (GWP) of approximately 2,088, meaning it traps roughly 2,000 times as much heat as CO₂ over a 100-year period. The American Innovation and Manufacturing (AIM) Act, signed in 2020, directed the EPA to phase down high-GWP refrigerants including R-410A.

2025 and beyond: A2L era. The EPA's Technology Transitions rule under the AIM Act set January 1, 2025 as the date after which manufacturers cannot produce new residential air conditioners and heat pumps using refrigerants above 750 GWP. R-410A (GWP ~2,088) is out for new equipment. The replacements — primarily R-454B and R-32 — have GWPs of 466 and 675, respectively. Existing R-410A systems can still be serviced; only new equipment manufacturing changed.

R-22: What to do if your system still uses it

R-22 systems were the standard for residential central air conditioning from roughly the 1970s through 2009. If your system was installed before 2010, it almost certainly runs on R-22.

Why R-22 repairs are so expensive

Because R-22 production and import are banned, the only legal supply comes from:

• Reclaimed refrigerant — recovered and cleaned from old systems
• Recycled refrigerant — reused from the same system during service

Supply is finite and shrinking. The market price for reclaimed R-22 has risen from roughly $10–$20 per pound before the ban to $50–$150+ per pound in many markets as of 2026. A small refrigerant leak might require 2–4 pounds of refrigerant to recharge. That's $100–$600 just in refrigerant, before labor or leak repair costs.

The real problem: the leak

The right response to an R-22 refrigerant recharge isn't "add more refrigerant." Refrigerant in a correctly operating system doesn't get "used up" — it circulates in a closed loop. If the system is low on refrigerant, there is a leak somewhere. The leak should be found and repaired. If the leak is in the compressor, evaporator coil, or condenser coil, the repair cost often approaches or exceeds the cost of full system replacement.

Should you repair or replace an R-22 system?

Bottom line on R-22: There is no path where R-22 systems get cheaper to maintain. The refrigerant supply shrinks every year, prices rise, and parts availability declines. A functioning R-22 system is fine to run. The moment it needs a significant repair, the math almost always favors replacement. See our HVAC cost guide for full repair vs. replacement numbers.

R-410A: Your system is fine, but watch the trends

If your central AC or heat pump was installed between roughly 2010 and 2024, it uses R-410A. The good news: R-410A is still available, prices are reasonable (though rising), and your system has years of serviceable life ahead if it's well-maintained.

What the 2025 phasedown actually means for you

The AIM Act's 2025 deadline applies to manufacturers, not homeowners or contractors. Specifically:

• HVAC manufacturers cannot produce new residential AC and heat pump equipment using R-410A after January 1, 2025
• R-410A refrigerant itself is still legal to produce, sell, and use for service and repair of existing systems
• Your R-410A system is fully legal to operate and maintain indefinitely
• Contractors can still purchase R-410A and recharge your system

What will change over time: the EPA's AIM Act targets an 85% reduction in total US HFC production and import by 2036. R-410A production will decline year over year. The likely effect on homeowners: R-410A prices will gradually increase, making refrigerant recharge more expensive as systems age. This is not an emergency, but it's a factor in replacement timing for older R-410A systems.

R-410A repair cost in 2026

R-410A refrigerant currently runs approximately $5–$20 per pound for wholesale supply, translating to $150–$500 for a typical recharge including labor. This is still reasonable — but watch this number over the next 3–5 years.

R-454B and R-32: The new refrigerants in 2025+ systems

If you're buying a new air conditioner, heat pump, or mini-split system today, it uses one of these refrigerants. Both are classified as A2L — mildly flammable — which is the biggest practical difference from the A1 (non-flammable) refrigerants that came before.

R-454B (sold as Puron Advance® by Carrier, Solstice® Plus by Honeywell)

• GWP: ~466 (78% lower than R-410A)
• Flammability class: A2L (mildly flammable)
• Operating pressures: Similar to R-410A but not identical
• Who uses it: Carrier, Trane, American Standard, Lennox, and most major brands

R-454B is the most widely adopted R-410A replacement in the US residential market. Its operating pressures and system configurations are designed to be as close to R-410A as practical, which made the transition manageable for contractors.

R-32 (used by Daikin, Mitsubishi, and others)

• GWP: ~675 (68% lower than R-410A)
• Flammability class: A2L (mildly flammable)
• Operating pressures: Higher than R-410A
• Who uses it: Daikin, Mitsubishi, and some other manufacturers, particularly for mini-splits

R-32 has been used in some markets (Europe, Asia) for over a decade and has a strong safety record when handled by trained technicians.

What "mildly flammable" means for homeowners

A2L refrigerants are categorized as mildly flammable. In practical terms:

• They have a much higher ignition point than propane or natural gas and require a specific ignition source, concentration, and airflow conditions to ignite
• Indoor equipment using A2L refrigerants has safety design requirements (leak detection, minimum air volumes)
• Technicians handling A2L refrigerants need updated recovery equipment and training — not all older contractors have made this investment

What it means for you: make sure any contractor servicing a 2025+ system has updated their tools and training for A2L refrigerants. It's a fair question to ask when getting quotes. See our guide on how to hire an HVAC contractor for the full checklist.

How to identify what refrigerant your system uses

You don't need to guess. Check the data plate on your outdoor condenser unit (the box outside your home). It will show:

• Model number and serial number — the serial number often encodes the manufacturing year
• Refrigerant type — labeled as "Refrigerant" or "Ref." on the plate (e.g., "R-410A" or "R-454B")
• Refrigerant charge — listed in ounces or pounds

If the plate is worn or unreadable, a licensed technician can identify the refrigerant type during a service call. Never mix refrigerant types without knowing exactly what's in the system.

Quick rule of thumb by installation year:

Refrigerant and the replacement decision

The refrigerant your system uses should factor into any major repair decision.

R-22 system + major repair needed

Run the numbers. Take the repair quote, add likely future refrigerant costs (assume prices continue rising), and compare to the total cost of a new energy-efficient system over 10 years. In most cases, replacement wins — especially with available IRA tax credits for qualifying heat pumps (up to $2,000 under the 25C credit, income restrictions apply). Review your options with our HVAC replacement timing guide.

R-410A system + refrigerant recharge needed

This is not a reason to replace on its own. R-410A is still available and reasonably priced. Fix the leak, recharge the system, and evaluate system age and condition for a longer-term replacement plan.

R-410A system + compressor or coil failure

This is where the replacement math gets interesting. A major R-410A system component repair runs $1,200–$2,800+. A new system using R-454B will be more energy-efficient (higher SEER2 rating), eligible for potential tax credits and utility rebates, and warrantied for 5–10 years on parts. If your R-410A system is 10+ years old, replacement is often the financially superior path. Our HVAC financing guide covers how to fund a new system if cost is a barrier.

New system purchase

You have no choice about refrigerant — any new system today will use R-454B or R-32. Focus instead on SEER2 rating, equipment brand, contractor warranty, and installation quality.

Questions to ask your contractor

When your contractor mentions refrigerant, here are the questions that separate informed technicians from everyone else:

1. "What refrigerant does my system use, and how much is it?" — Should reference the data plate
2. "Where is the refrigerant leak?" — Low refrigerant always means a leak; any technician who just recharges without finding and fixing the leak is not doing the full job
3. "Are you certified to handle this refrigerant?" — EPA Section 608 certification is required to purchase and handle refrigerants
4. "Are your tools updated for A2L refrigerants?" — Critical for 2025+ systems
5. "Will this repair cost more than 50% of replacement?" — The standard rule of thumb for the repair-vs-replace decision

For a complete contractor vetting checklist, see How to Hire an HVAC Contractor. For after-hours failures, see our emergency HVAC repair guide.