Are there any Drop-In Replacement Refrigerants for R-12?
No. A number of refrigerants other than R-134a have been listed by EPA as acceptable under its Significant New Alternatives Policy (SNAP) program, or are under SNAP review. The SNAP program evaluates substitutes only for their effect on human health and the environment, and not for performance or durability. None of these refrigerants have been endorsed by the OEMs for use in vehicles, and few have had extensive testing in a wide range of vehicle models. While some manufacturers of alternatives may be marketing their products as “drop-ins,” keep in mind that because of the EPA regulations for different service fittings and labeling, there is no such thing as a refrigerant that can literally be dropped in on top of the existing R-12 in the system. Furthermore from a engineering stand point, none of the claimed refrigerants have demonstrated drop-in performance! For more information on the SNAP requirements and on which alternatives have been reviewed, accepted, or deemed unacceptable by
