EPA is still considering new HFO-1234yf retrofit options for some heavy-duty MVAC systems
CheckNo new retrofit permission is asserted yet. Shops that retrofit heavy-duty pickup or complete heavy-duty van A/C systems should monitor EPA’s SNAP Rule 27 for a final rule and follow only refrigerants and use conditions that are currently approved.
Applies toGeneral mechanical, Mobile repair, Mixed services
Details & evidence
EPA’s April 2026 supplemental SNAP Rule 27 proposal would list HFO-1234yf as acceptable, subject to use conditions, for retrofit of motor-vehicle A/C systems in heavy-duty pickup trucks and complete heavy-duty vans. EPA’s current SNAP regulations page still lists the action as a supplemental proposed rule, not a final rule.
Official evidenceU.S. EPA — SNAP proposed and final rules ↗ · verified Sep 19, 2026