My local A/C repair shop tells me that they often use FR-12 in older systems like mine ('91 Explorer). They informed me that FR-12 is a blend of R12 and R134a.
What the shop didn't know was that my compressor was replaced in Dec of '98 and that a placard on the this compressor states, "Use R134a Only". However, since the valve fittings on the A/C system are still the older R12 threaded type, I'm GUESSING that my A/C is still filled with R12.
Knowing that I have an updated compressor, and that A/C shops sell FR-12, I'm now asking myself if there's any reason I can't simply add R134a to my R12 system??
Has anyone ever done this before??
Any help is appreciated,
Mike