# R-125/R-134a/R-600a (28.1/70.0/1.9) — HVAC refrigerant replacements: retrofit compatibility, safety class, GWP and lubricant

For R-125/R-134a/R-600a (28.1/70.0/1.9), trade name(s) is NU-22 old composition; retrofit / new is R/N; ashrae safety class is A1; gwp is 1,990; listing status / notes is Acceptable, verified against its source on 2026-08-11.

- **Refrigerant:** R-125/R-134a/R-600a (28.1/70.0/1.9) _(verified: appears in the quote below)_
- **Trade name(s):** NU-22 old composition _(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:** 1,990 _(verified: appears in the quote below)_
- **Listing status / notes:** Acceptable _(verified: appears in the quote below)_

## What the source says

> R-125/R-134a/R-600a (28.1/70.0/1.9) | NU-22 old composition | R/N | 0 | 1,990 | A1 | <https://www.govinfo.gov/content/pkg/FR-2010-06-16/pdf/2010-14510.pdf> June 16, 2010 (pdf) (229 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/).