For years, HVACR technicians have been used to primarily working with nonflammable (A1) refrigerants, such as R-410A, R-22, and R-404A. Now that HCFCs are being phased out and there is growing concern over the high GWP of some HFCs, new lower-GWP alternatives have been developed to take their place. However, some of these new refrigerants, such as R-32 and R-454B, are mildly flammable (A2L), which means additional safety precautions must be followed when handling them.
That includes using a recovery machine designed specifically for A2L refrigerants. Most standard recovery machines are designed to handle A1 refrigerants, which means they may not have the safety features required for mildly flammable refrigerants.