R-454B vs R-32 Heat Pumps: Which Refrigerant Should You Choose?

Quick answer

Both R-454B and R-32 are good, safe, efficient refrigerants, and the choice is rarely worth worrying about. Pick the heat pump that’s best for your home, installer and budget; the refrigerant comes with it. R-454B has the lower climate impact (GWP 466 vs 675) and is the default in most US ducted central systems. R-32 is a simple single-component refrigerant used by most ductless mini split makers and has a long global track record. What actually matters more is installer experience with these newer refrigerants, proper sizing, and the equipment’s efficiency ratings.

R-454B vs R-32 vs R-410A at a glance

	R-454B	R-32	R-410A (outgoing)
Global warming potential (GWP)	~466	675	~2,088
Composition	Blend: ~69% R-32, ~31% R-1234yf	Single component	Blend (R-32 + R-125)
Safety class	A2L (mildly flammable)	A2L (mildly flammable)	A1 (non-flammable)
Typical use in the US	Most ducted central heat pumps and ACs	Most ductless mini splits; some ducted brands	Pre-2025 equipment
Operating pressures vs R-410A	Very similar	Somewhat higher	—
Can be added to an R-410A system?	No	No	—
Status for new equipment	Allowed	Allowed	No new manufacturing since January 1, 2025

GWP figures are the commonly cited values (ASHRAE Journal).

Why heat pumps switched refrigerants

The 2020 American Innovation and Manufacturing (AIM) Act directs the EPA to phase down high-global-warming-potential HFC refrigerants. Under the EPA’s Technology Transitions rule, new residential and light-commercial air conditioners and heat pumps must use refrigerants with a GWP below 700. R-410A, at about 2,088, didn’t make the cut; R-454B and R-32 do.

The timeline, including the 2026 change

Date	What happened
January 1, 2025	Manufacturers stopped producing and importing new R-410A residential split ACs and heat pumps
January 1, 2026	Original deadline to install leftover R-410A split systems. EPA announced in December 2025 that enforcing it would be a low priority
May 21, 2026	EPA finalized a rule removing the January 1, 2026 installation deadline for residential and light-commercial R-410A equipment manufactured or imported before 2025, so existing inventory can be installed until it runs out (ACHR News)
July 27, 2026	The new rule took effect (NAHB)
Ongoing	R-410A remains legal for servicing existing systems, but supply is shrinking under the HFC phasedown, which tends to push prices up

Exception: New York. State regulation Part 494 keeps the January 1, 2026 installation deadline in force, so leftover R-410A systems can’t be installed there (ACCA). Other states and local codes may have their own rules.

What this means for you: if you’re buying a new heat pump, it will almost certainly use R-454B or R-32. Some contractors may still offer leftover R-410A units; see the section below before you accept one.

The practical differences

Efficiency and performance

On paper, both refrigerants are efficient, and modern systems using either can reach high SEER2 and HSPF2 ratings. In practice, the equipment design matters far more than the refrigerant: compressor, coils, controls and installation quality decide real-world efficiency. Compare heat pumps by their SEER2, HSPF2 and (in cold climates) 5°F capacity and COP, not by refrigerant.

A few technical notes:

R-32 is a single component, so it behaves the same throughout the system and can be topped off after a small leak without changing its makeup. It runs at somewhat higher pressures and discharge temperatures, which manufacturers design around.
R-454B is a blend with a small temperature “glide” (about 1.4°F), so it must be charged as a liquid, and a leaking system is usually recovered and recharged rather than topped off. Its pressures are very close to R-410A’s, which made it an easier transition for many ducted product lines.

Climate impact

R-454B’s GWP of about 466 is roughly 31% lower than R-32’s 675. Both are dramatic improvements over R-410A. For a typical home charge of a few pounds, the difference between the two is small next to the energy a heat pump saves.

Service and refrigerant cost

Both require technicians trained in A2L refrigerants and compatible tools and recovery cylinders.
R-454B supplies were tight when the transition started in 2025, and its per-pound price has generally been higher than R-32’s. Prices change, so ask your installer what a typical recharge costs.
Neither can be put into an R-410A system, and neither can be mixed with the other.

Safety: what “A2L” means

Both refrigerants are classed A2L: low toxicity and mildly flammable. They’re much harder to ignite than propane-type (A3) refrigerants and burn slowly if they do. Equipment and building codes are built around that:

Many ducted A2L systems include refrigerant leak sensors in the indoor unit, which turn on the blower to disperse any leak.
Installers follow updated codes for line sets, brazing and charge limits.
In normal home use, A2L heat pumps are considered safe; millions of R-32 mini splits have been used worldwide for over a decade.

The practical takeaway: hire an installer who has done plenty of A2L installs and follows the manufacturer’s instructions exactly.

Which brands use which refrigerant?

The industry split roughly along product lines: most US ducted central-system makers chose R-454B, while most ductless mini split makers chose R-32.

Mostly R-454B	Mostly R-32	Mixed or model-dependent
Carrier, Bryant (Carrier calls it Puron Advance)	Mitsubishi Electric (ductless)	Daikin and Goodman (Daikin-owned): many R-32 products, some R-454B
Trane, American Standard	Fujitsu	Bosch, Gree, Midea-made brands: varies by series
Lennox	LG
Rheem, Ruud	Panasonic
York / Johnson Controls
DIY lines: MRCOOL, Zone Air; budget lines such as Pioneer Diamante Pro

This reflects published product information as of 2026 and can change by model and year (Nuwatt Energy; Central AC Install Cost). Check the refrigerant on the exact model’s spec sheet or data plate, especially if you’re mixing an outdoor unit and indoor unit from different series.

Should you buy a leftover R-410A heat pump?

Since EPA lifted the installation deadline in 2026, some contractors are selling remaining pre-2025 R-410A inventory, sometimes at a discount. It’s legal outside New York, but weigh the downsides:

Consider	Why it matters
Future repair costs	R-410A supply keeps shrinking under the HFC phasedown, so recharging after a leak is likely to get more expensive over the system’s 12–15-year life
Rebates	Some programs exclude R-410A equipment. Mass Save, for example, removed R-410A heat pumps from its qualified list in 2026
Age of the equipment	“New” leftover stock may have sat in a warehouse for a year or more; confirm the manufacture date and that the warranty starts at installation
Matching parts later	Replacing just the indoor or outdoor half of an R-410A system in the future will get harder as inventory dries up
Resale and buyer perception	Future buyers and inspectors may see an R-410A system as outdated

Bottom line: a leftover R-410A unit can make sense only with a meaningful discount, no rebate you’d be giving up, and a full manufacturer warranty. Otherwise, choose R-454B or R-32.

Already have an R-410A system?

You don’t need to do anything. Your system is legal to run and to repair, and R-410A refrigerant remains available for service. When it eventually needs replacing, plan on switching both the indoor and outdoor units to a new A2L system: R-454B and R-32 aren’t drop-in replacements, and new line sets are often recommended. If a major repair (compressor or a large leak) comes up on an older R-410A system, rising refrigerant costs are one more reason to compare repair against replacement.

Frequently asked questions

Which is better, R-454B or R-32?

Neither is clearly better for homeowners. R-454B has a lower GWP and dominates US ducted systems; R-32 is simpler to service and dominates ductless mini splits. Choose the heat pump and installer, not the refrigerant.

Is R-410A banned?

No. New R-410A residential systems stopped being manufactured in 2025, but existing systems can still be used and serviced. In May 2026 the EPA also removed the deadline for installing leftover pre-2025 R-410A equipment, except in New York, which kept its own deadline.

Are R-454B and R-32 safe in my home?

Yes, when installed to code. Both are A2L (mildly flammable) refrigerants, and systems include safeguards such as leak sensors on many ducted indoor units.

Can I put R-454B or R-32 in my R-410A system?

No. They aren’t drop-in replacements. Switching refrigerants means replacing the outdoor and indoor units, and often the line set.

Do R-454B and R-32 heat pumps cost more?

New equipment costs rose somewhat during the transition, and A2L installs require updated tools and training. Price differences between R-454B and R-32 systems mostly reflect the brand and model, not the refrigerant.

Is R-454B in short supply?

Supplies were tight in early 2025 as the transition began. Ask your installer about current availability and the typical cost of a recharge.

Related guides

SEER2 and HSPF2 Ratings Explained: Which Numbers You Actually Need
Heat Pump Installation Cost in 2026: Real Prices by Home Size and System Type
Heat Pump vs Central Air Conditioner: What to Install When Your AC Dies
Massachusetts Heat Pump Rebates 2026: Mass Save Amounts and How to Apply
Best DIY Mini Split Systems 2026: Top Picks by Room Size
Heat Pump Blowing Cold Air in Heat Mode: 9 Causes and Fixes

This guide is general information. Refrigerant rules can change and vary by state; confirm current requirements with your installer. Refrigerant work must be done by an EPA-certified technician.