Glossary · Heating, cooling & ventilation
Refrigerant (R-454B, R-32, R-410A)
Also called: refrigerants · R-454B · R-32 · R-410A · R-22 · low-GWP refrigerant
The fluid a heat pump or air conditioner pumps around to move heat; newer systems use R-454B or R-32 instead of the older R-410A.
What it means
The refrigerant absorbs heat as it evaporates in one coil and gives it off as it condenses in the other, which is how a heat pump moves heat. Many refrigerants are strong greenhouse gases, rated by their global warming potential (GWP), so US rules have moved new home systems from R-410A (GWP 2,088) to R-454B (465) and R-32 (675).
Why it matters in an audit
The refrigerant on a quote shows whether you're being offered current equipment or older R-410A stock, and some rebate programs accept only low-GWP models.
Typical numbers
Reference values with their sources. Your auditor’s report gives the figure for your own house.
| What | Value | Source |
|---|---|---|
| Global warming potential (EPA, 100-year) | R-410A 2,088; R-454B 465; R-32 675 | epa.gov ↗ |
| US limit for new home air conditioning and heat pump systems | GWP 700 or less for systems built from parts made or imported from Jan 1, 2025 (EPA Technology Transitions rule) | epa.gov ↗ |
| US change, May 2026 | EPA removed the installation deadline for systems whose parts were all made or imported before Jan 1, 2025, so remaining R-410A stock can be installed until it runs out | epa.gov ↗ |