Your 1993 Buick should use R134A. You do not need to be certified to purchase R134A refrigerant. But you do need to be certified to purchase R12.
To find out whether your Buick has R12 or R134A, Take a look at the connectors. If it's threaded then it's R12. If it has quick Connects. Then your vehicle takes R134A and doesn't need to be converted.
But if it has the threads it needs converted and I highly recommend you take it to a certified A/C tech to get the Job done right. You don't want to overcharge the system.
If it does have R12 it needs to be recovered by a certified A/C Tech. And a vacuum also needs to be pulled on the system. This is to remove non condensable gases from the system.
Also to properly recharge the system the A/C needs to be set to on and max cooling if you have it. Please note. If your vehicle is out of refrigerant the compressor will not kick on until it's half full.
I'm a certified Motor Vehicle A/C Tech so I know what I'm talking about.
It came with R12 Freon. As R12 is cost prohibitive, have the unit converted to R134a refrigerant or a similar substitute.
Would have been built for R12, can be converted to R134a.
OEM refrigerant which came installed in 1993 was Freon R12. I suggest you convert it to R134a if it has not already been converted. R12 is far to expensive.
All vehicles after 1993 I believe use R-134a
It was built with R12, can be coverted to R134aIt was built with R12, can be coverted to R134a
Pre 1993 was built with R12, 1994 and later uses R134a.
Would have been built for R12, can be converted to R134a.
No. They use R22 or R410A. Cars use R12 (before 1993) and R134A (after 1993). You cannot mix them together.
1994 and later is R134a1993 and before was R121994 and later is R134a1993 and before was R12
You can't. You have to be Section 608 certified and licensed to buy CFC12 (R12) in any quantity. Your best bet is to either convert it to R134a or R414b.
R134a . All vehicles after 94 went from R12 to R134a
A 93 would use R12 if it has not yet been converted to R134a. Only authorized technicians are allowed to handle R12.