Refrigeration basics: refrigerants

The choice of refrigerant affects efficiency, safety and compliance with environmental requirements. The trend is towards a lower global warming potential (GWP).

Natural refrigerants (R290 propane, CO₂) deliver a low GWP, but call for attention to fire and explosion safety and, in the case of CO₂, to higher operating pressures.

HFC blends (R448A, R449A) are a transitional option with a moderate GWP that is convenient for retrofitting existing systems.