newbie needs a/c help

[DaleInTN]

I was wondering if anyone knows how to tell if an r12 system has been changed over to an r134 system?

[Chobobulous]

The valves you put the freon in will have something screwed onto them. Itmakes it alot bigger. If the valve looks like the valve you put air in your tires with it is still r12.

[KingFish]

Look at the fill valves, the ones with the caps. The R12 systems have the threads on the outside and the R134 have them on the inside. IIRC.

[MasterTec]

This should clear it up for you.