But clearly, propane (R290) is the way of the future for residential air conditioning, as a drop-in replacement for R22 and R12. Quoted Text Here Again, R22 is (was) one of the most efficient working fluids - equivalent to R134. Not sure how it compares to R12. sharepoint online tutorial youtube, Select the SharePoint tile on the on the Microsoft 365 home page, or in the app launcher. For more information, see Where to sign in to Microsoft 365 . a) replacement for CFC-12 and R-500 in the Industrial Process Refrigeration (R) b) replacement for CFC-12 and R-500 in the Household Refrigerators (R) c) replacement for CFC-12 and R-500 in the Household Freezers (R) (R) = Retrofit Uses (N) = New Uses Similar : Autofrost, GHG Refrigerant-12, GHG X3, R-406a, GHG-406a Physical properties: Jul 26, 2002 · Re: R-12 replacement, AUTOFROST R134a is the only recommended and accepted sustitute for R12 conversion. Make sure to do your homework on this stuff (autofrost) before you put it in your system. Some R12 substitute are custom blends that can do more harm to your A/C system than good. But cross-contamination between R-12 and R-134a was also found in 15% of the tanks. The most cross-contamination (29%) was discovered in used car dealers. RETROFIT TO r-134A OR NOT? Use R-12 in all R-12 systems as long as it is available because R-12 provides the best cooling performance in these applications.