Automotive Air Conditioning Information Forum

JohnHere wrote: ↑Wed Apr 20, 2022 3:20 pm I can relate. I think most of us on here have gotten headaches with problems like this. I'd still start with replacing the HPRV. They're cheap, and at least then we could rule it out.

Do I understand correctly that you can charge the system only to a reading of 110 PSI on the high side (when it should be about 160 PSI at full charge and at 71 degrees ambient) before the HPRV starts to release? If so, the reduced high-side pressure could be the reason why the compressor isn't cycling yet. How much refrigerant does it take before the HPRV starts to release?

DetroitAC wrote: ↑Thu Apr 21, 2022 4:43 am It seems very improbable to have two defective PRV, especially the OP says he installed NEW Denso compressor. I'm doubtful it's what is really going on. Maybe try a different gauge set, yours is not opening maybe, gage stuck, valve not opening, 110 on yours is in reality 550 psi? I'm just guessing of course

PRV can leak after the first activation, but I don't know how they could open at such a wrong pressure. It's a preloaded spring putting a force on a ball, very reliable to open at the set pressure. not very reliable to seal completely so they are sometimes potted when new.