My AC blows warm, I need to charge it and the previous owner said it was a 134A conversion but I am not sure how to tell. Any thoughts/knowledge appreciated. Hope the picture helps.

 

Looks like a conversion to me.

Try adding a can of cold juice to the low side (blue cap) and see what happens.

 

Generally you can tell by the 134a adapters screwed on the service ports. Technically a person is supposed to leave the adapters on the car. But now sometimes you get an originality freak, that hates the way the adapters look, and uses non-traditional refrigerants, in which case you can have an R12 system charged with Betty Crocker fudge brownies.

 

i would probably rather have the brownies than the 134, Thanks.

 

Same here. I like brownies.

Seriously, there are several good drop-in replacements for R12 short of converting to R134a. I can't say I've tried them all, but the one I did use worked just fine.