Since it is not compatible with mineral oils, it should be used with polyolester or polyolalkalinglycol based oils. R404a is a near-azeotropic mixture consisting of R32 and R125 (50% by weight) and is considered an alternative to R22.

Theoretical thermodynamic properties are not as good as R22. However, its heat transfer property is quite good. In the R22 – R410A conversion, the system needs to be redesigned.