A/C question

rockyracoon

10 Year Member
Nov 23, 2005
874
27
49
margate NJ
I just charged my car with freeze 12.Im getting around 27 PSI on the low side.The car is blowin out cool/cold air but I can tell it needs to be a little colder.anyone know if 27 psi is acceptable? on the little gauge im using the normal range goes fron 24 to 44 psi.I charged 2oz of oil and 36 oz of freeze 12.the car was evaced for a coupla hrs and also I used nitrogen for leaks, and purged with the N2 for a few mins.BTW the car was never converted to 134a .thats kinda why I went with the freeze 12.
 
From what I've seen 27psi is okay but I've seen 35 and even 40 on some systems. Can't remember how much R-12 the mustang takes though. Mine was converted to R-134a and took 32oz of R-134a. I think that the ratio of R-12 to R-134a is 80% (1oz R-12 to 0.8oz R-134a) as a baseline but you can add more than that. For my car that comes out to 38.4oz of R-12. You should be okay to add a little more but not a whole lot(3-4 oz's).