Kinda OT: R12 vs R-134

[Hector]

My 1990 mazda decided to stop blowing cold air. It's been years since the system has been recharged. How can you tell if the system has been converted from R12 to R-134?

[JonE]

I think they sometimes put a sticker on the AC system somewhere. Also, the size of the 134 refill fittings are different than the R12 fittings. I don't know the sizes, but the newer R134a system hose fittings for replacing refridgerant won't fit on the R12 fittings.

[Mr Project]

Legally they're supposed to put a retrofit sticker somewhere. Also the fittings are different, and there are refrigerant detectors that an AC shop should have if it's really giving you fits.

[1992 BMW 535i]

Your car most definitely did not come with R-13A, and Jon is correct when he says that the fittings are different. Problem is that there are aftermarket refill kits that will allow you to use your existing fitting when recharging the system.

[Hector]

a bit more time. Right now it hasn't been that hot here in SoCal. Pepboys charges $122 for the conversion and $98 if it's been converted already. Also, the guy at Autozone said that I can purchase a kit for 39 bucks to recharge the system. I'll think about this more later after I'm done resurrecting Frankenstein (e34.)

[winfred]

we see so many cars that don't have any fittings or stickers it's not even a suprise any more, to protect our ac recycler we use a freon identifier on everything and a lot of the time come up with contaminated systems that have stickers and fittings

Legally they're supposed to put a retrofit sticker somewhere. Also the fittings are different, and there are refrigerant detectors that an AC shop should have if it's really giving you fits.