609 MVAC cert is what I have. Been 20 years since I’ve done any AC work though aside from topping off with a small can of 134a.
Yep.... IMACA was doing them early on then MACS took over. Absolutely despise the new refrigerants as R-12 is the king. There are not many R-134a systems that I can consistently get into the low 40’s.
Funny thing, long ago the EPA classified as illegal any refrigerant that is considered flammable so why the HFO1234yf?
Go figure.