This SAE Recommended Practice applies to refrigerant blends (multicomponent refrigerants) intended for use as retrofit refrigerants to replace CFC-12 (R-12) in mobile air-conditioning (A/C) systems. Since the composition of non-azeotropic refrigerant mixtures changes as refrigerant is lost, either through the vapor phase or the liquid phase, the method of charging A/C systems is important. The purpose of this document is to determine the proper refrigerant phase, liquid or vapor, for system charging by relating system performance changes to the charging method. This document is complete only when combined with the requirements of SAE J1657.
The original proposal to stabilize this document was balloted in March of 2013. Five voters recommended that instead the document be removed from circulation. The document applies to R12 refrigerant which was phased out of automotive use in 1995. The document should be cancelled to make it clear that future replacement refrigerants are not a replacement for R12, but replacements for R134a which is the current refrigerant used in most automotive applications today.