Posted 9/14/2021 18:54 (#9220356 - in reply to #9220303) Subject: RE: R12 AC system top off?
Hagen Brothers farms,Goodrich ND
The only sure way is to buy R12 refrigerant or do a conversion to R134a, or totally replace the refrigerant with a substitute. The replacement refrigerants may be reluctant to tell you if their product can be mixed with R12, because it USED to be illegal to mix refrigerants, maybe still is. I have read some claim they topped off R12 systems with R134a, although their not supposed to be compatible. I have done a lot of conversions from R12 to R134a with ester oil added, has been 100% success and is available everywhere for still pretty cheap. Just don't flush the system unless the compressor failed, as the coating of R12 mineral oil does a good job of sealing R134a in hoses designed for R12.