R12, if still available at your local parts store (requires a license), is very expensive. It is cheaper to retrofit the system to use r134a.
It originally came with Freon (R12). Unless it has been converted then it will still contains R12. I suggest you have it converted to R134a, as Freon is so very expensive and hard to find.
R12 And if you still have this change over to 134a instead of buy r12
It was built with R12, can be coverted to R134aIt was built with R12, can be coverted to R134a
Mineral oil is used with all R12 systems.
The cost of R12 varies a great deal. The use of R12 is illegal in some places and requires certification in others. It is estimated that a pound of R12 currently costs approximately $20 US dollars.
First of all, you don't use R12. Rather, R134 which has the oil included.
They didn't use R12 in 1995 - they'd all gone to R134a by then. Which is fortunate for you, because you can't even buy small cans of R12 without Section 609 certification.
If if it a 1995 or older then it came with R12 installed. 1996 can be R12 or R134. 1997 up, it has R134/R134a. If you suspect it had R12 look for a label somewhere on the A/C unit signifying it has been converted. If you find it has R12 and is leaking and needs repairing, after the leak is repaired, convert it to R134a. R12 is far too expensive to use.
R12
r12 or 134a
r12