# R-424A — HVAC refrigerant replacements: retrofit compatibility, safety class, GWP and lubricant For R-424A, trade name(s) is RS-44; retrofit / new is R/N; ashrae safety class is A1; gwp is 2,440; listing status / notes is Acceptable, verified against its source on 2026-08-11. - **Refrigerant:** R-424A _(verified: appears in the quote below)_ - **Trade name(s):** RS-44 _(verified: appears in the quote below)_ - **Retrofit / new:** R/N _(verified: appears in the quote below)_ - **ASHRAE safety class:** A1 _(verified: appears in the quote below)_ - **GWP:** 2,440 _(verified: appears in the quote below)_ - **Listing status / notes:** Acceptable _(verified: appears in the quote below)_ ## What the source says > R-424A | RS-44 | R/N | 0 | 2,440 | A1 | September 28, 2006 (pdf) (183 KB) | Acceptable | ## Source - https://epa.gov/snap/substitutes-residential-and-light-commercial-air-conditioning-and-heat-pumps Last verified: 2026-08-11. Review by: 2027-08-11. Part of [HVAC refrigerant replacements: retrofit compatibility, safety class, GWP and lubricant](https://referencesource.org/hvac-component-refrigerant-compatibility/).