R12 Freon substitute tip for car buffs - Save yourself $$$

[Barnaby W. Füi]

Originally posted by: Lithium381
you guys with your AC....stop whinning, i don't have AC....:\ not that it bothers me, i just roll the window down and suck it up.....how much does it cost to get more freon?

Same here. 24 year old car, the compressor was dead long ago. "Roll the window down and suck it up", no truer words were ever spoken

 

On the R134a conversion subject.....

I know the oil used with R12 isn't compatible with the R134a.....how do you get all of it out of the system?

Also, I know an R134a system typically runs at around twice the pressure of an R12 system, what do you do about this with a changeover?


JC

To properly remove the R 12 oil, disconnect the A/C compressor, remove it from the vehicle and let it sit upside down in a drain pan, this will remove about 90% of the old oil, if you want all the old oil removed, replace the receiver/dryer.

Do not forget to recharge with PAG oil

It is imperative that you draw at least twenty inches of vacuum minimum to remove all the moisture and contaminants, if this is not done, drastic losses in cooling efficiencies occur.

R 134a does not run at twice the pressure of R 12, R 134a has a different boiling point, only a slight increase in pressure is realized, this is why it is imperative that you do not fill the system to 100% capacity when refilling with R 134a.

 

[Eli]

Oh, I dunno.. I don't know anything about AC, he said 4oz in his first post, I assumed thats what most ac compressors took

 

Eli

 

[NutBucket]

R12 isn't that expensive. Its about $35 a half-pound according to my friend who's also a mechanic. I had him evacuate my R12 in preperation for my motor-swap. Pulled out 1.5 pounds; system is full at about 2 pounds. For $35 and some new seals I'm sticking with R12. I love my meat-locker Honda A/C