HVAC Systems · Refrigerants
A2L Refrigerant
ASHRAE 34 safety classification for refrigerants that are mildly flammable (lower flammability "2L") and have low toxicity ("A"). Includes R-32 and R-454B, the replacement refrigerants for R-410A under EPA AIM Act phasedown. A2Ls have low ignition energy thresholds and require trained handling; charge limits, leak detection, and equipment design rules differ from A1 (non-flammable) refrigerants.
Safety note
A2L refrigerants are mildly flammable. Charging, recovery, and brazing on A2L systems require A2L-rated equipment and EPA 608 Type II certification with updated training. Sparking tools and open flames are prohibited during system service.
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