Cooling

R-454B: what it is and what it means for your system

Licensed professional required

Only EPA Section 608 certified technicians may purchase or handle refrigerant for stationary equipment.

R-454B is a HFO/HFC blend refrigerant with safety classification A2L. R-454B has an EPA exchange value of 465, under the 700 limit, which is why it is one of the two refrigerants most new residential systems now ship with. It circulates in a sealed loop and is not consumed, so a system low on charge has a leak rather than a need for a top-off.

Type
HFO/HFC blend
Safety class
A2L
GWP (EPA)
465

What should you know about R-454B?

  • R-454B has an EPA exchange value of 465, under the 700 limit, which is why it is one of the two refrigerants most new residential systems now ship with.
  • It is classified A2L — mildly flammable. That changes service procedures, leak detection, and in some cases charge limits, but it does not make the equipment unsafe to own or operate.
  • A2L service requires equipment and training a shop may not have had five years ago. It is a fair question to ask a contractor whether their technicians are trained on A2L refrigerants.

What about its GWP figure?

The EPA regulatory exchange value for R-454B is 465. EPA's regulatory global warming potential values under the AIM Act are "exchange values" numerically equal to the 100-year GWPs in the 2007 IPCC Fourth Assessment Report. Other publications sometimes quote values from newer IPCC reports, which differ. The figures on this page are EPA's regulatory values, because those are the ones the thresholds are measured against.

Composition: 68.9% R-32 / 31.1% HFO-1234yf.

A2L class. Mildly flammable. That changes service procedures and leak detection, but it does not make the equipment unsafe to own or operate.

What is happening with refrigerants?

This is the part of the industry that moved most between 2023 and 2026, and the part with the most outdated content. Three things shifted at once: R-22 production ended, a GWP limit took effect for newly manufactured equipment, and EPA revised the installation deadline in May 2026.

What actually drives the cost?

We publish no national average price, and the reason matters: an average across every house, region and system type is not a number you can act on. A replacement that includes duct modification, an electrical upgrade and a permit is a different job from a straight swap, and both read as “system replacement” on a one-page proposal.

What actually drives your number:

  • Equipment capacity and tier, which should come from the Manual J rather than the old nameplate.
  • The ducts — whether they can move the air the new equipment needs, and what it costs if they cannot.
  • Electrical work, if a circuit or panel change is required.
  • Permit and inspection, usually required.
  • Refrigerant — current equipment uses R-454B or R-32; remaining pre-2025 R-410A stock may price differently.

What a bid should itemise · operating cost calculator.

What should you know about refrigerant?

Refrigerant circulates in a sealed loop. It is not consumed the way fuel or oil is, so a system that is low on charge has a leak. Adding refrigerant without finding and repairing that leak treats the symptom, vents the new charge over the following weeks, and costs you the same money again next season.

It is also regulated. Only Section 608 certified technicians may purchase refrigerants intended for use with stationary refrigeration and air-conditioning equipment. The restriction covers ozone-depleting substances and non-ozone-depleting substitutes — including HFCs — in cylinders, cans or drums. Wholesalers must record the purchaser's name, the date of sale and the quantity.

There is one exception that confuses people: small cans of refrigerant for vehicle air conditioning are still sold without certification. That exception is for cars and does not extend to the equipment in your house.

For new equipment, the 700 GWP limit in force since January 1, 2025 is why current systems ship with R-454B (GWP 465) or R-32 (GWP 675) rather than R-410A (GWP 2088). R-410A inventory built before 2025 can still be legally installed — EPA removed the installation deadline on May 21, 2026. The full timeline.

Which efficiency numbers can you actually compare?

If you are comparing efficiency figures, check which generation they belong to first. On January 1, 2023 DOE changed the test procedure and renamed three metrics: SEER became SEER2, EER became EER2, and HSPF became HSPF2. The current procedure measures at a higher external static pressure, much closer to what equipment meets once installed in a real house on real ductwork.

DOE is explicit about the consequence: “Although SEER2, HSPF2, and EER2 ratings are similar to ratings using the original metrics, they are not directly comparable. Compliance with the new standards for each model must be determined based on its measured SEER2, HSPF2, or EER2.” In practice: a SEER figure from a 2019 article cannot tell you whether a quote reading SEER2 is good, bad or identical.

That is why we publish no conversion factor. We do not publish a SEER-to-SEER2 conversion factor. DOE states that ratings on the new metrics are "not directly comparable" to ratings on the original metrics, and that compliance must be determined from the measured SEER2, EER2 or HSPF2 value. Approximate multipliers circulate widely, but they vary by equipment type and configuration, and using one to compare an old article's number against a number on today's quote is how homeowners end up believing they were offered less efficiency than they were. Compare like with like: ask for the SEER2 figure, and check it against the AHRI certificate.

The nationwide minimum for a split-system air conditioner is 13.4 SEER2, and for a split-system heat pump 14.3 SEER2 with 7.5 HSPF2. What each metric measures · minimums by region and state.

What should a bid show you?

Three bids rarely quote the same job, so comparing headline price compares three different things. The one that was done properly shows its work, and you can check it line by line:

  • Model numbers for the outdoor unit, indoor coil, and air handler or furnace.
  • The AHRI reference number for that exact combination. A rating applies to a matched system, not to an outdoor unit on its own.
  • The SEER2 and, on a heat pump, the HSPF2 of that combination.
  • The Manual J result the sizing came from.
  • The measured static pressure and any duct work included.
  • The permit, and who pulls it.
  • Labour warranty, separate from parts, and whether registration is required.

The full red-flags checklist.

How can you verify any of this yourself?

Everything regulatory on this site traces to a primary source and carries the date it was read: DOE for efficiency standards, EPA for refrigerants and Section 608, the IRS for tax credits, and ACCA for load calculation. The sources for this page are listed at the end with the date each was consulted.

If you find a different figure elsewhere, check two things before deciding which to believe: whether the page says which generation its efficiency metric belongs to, and whether it carries a visible review date. Most of the outdated content in this category fails both tests.

Sources (6)
  1. U.S. Environmental Protection AgencyTechnology Transitions HFC Restrictions by Sector (accessed 2026-08-17)
  2. U.S. Environmental Protection AgencyFinal Rule: Reconsideration of Certain Regulatory Requirements under the Technology Transitions Provisions of the AIM Act (May 21, 2026) — fact sheet (accessed 2026-08-17)
  3. U.S. Environmental Protection AgencyTechnology Transitions GWP Reference Table (accessed 2026-08-17)
  4. U.S. Environmental Protection AgencyRefrigerant Sales Restriction (Section 608) (accessed 2026-08-17)
  5. U.S. Environmental Protection AgencyFrequent Questions on the Phasedown of Hydrofluorocarbons (accessed 2026-08-17)
  6. U.S. Environmental Protection AgencyPhaseout of Ozone-Depleting Substances (accessed 2026-08-17)

By HVACBuddy Editorial Team. Last reviewed: . Verified: