r-22 conversion to 421a choice refrigerant
fellas this is the replacement for r-22, no many parts house carry it, but you have a EPA card and are a legitimate business I will sell it to. I have used it for years to years there is no decrease if eff, no oil changes required.
david broome
Conversion
how about TXV and/or orifice changeout due to new superheat readings w/ the 421a?
very simple
if its r-22, 410a, or 421a tx valve cooling mode use sub cooling. if ts orfice, cap tube super heat. In the cooling mode always use subcooling on tx valves