AC Retrofit Questions

[ProjectH22]

I have read some threads on here about converting our R12 systems to R134a, but most threads are very old and none of them mention the now readily available conversion kits. Right now on Rockauto, I can get a conversion kit for $200. It includes a new compressor that is made for R134a, a seal/gasket set, the receiver/drier, expansion valve and oil for the compressor.

My AC currently works (just not good at all) so I know that the compressor hasn't blown up. Could one just compressor, gasket and those other components and then vacuum the system and recharge or do I need to disassemble the entire system and clean every individual part? If I need to do all of that extra stuff, I think I just will go without.

[deevergote]

It’s best to replace every part, as the two refrigerants are not at all compatible. I wouldn’t trust being able to clean out every part sufficiently. I researched converting my Miata, and ultimately decided it was far too involved to bother.

[adecanmin]

My was converted to r134a. It is possible to get enough of the old oil out using compressed air. My original compressor blew a seal so I was able to get a used compressor off the a newer Honda that was designed for r134a. I had to swap out the manifold. The pulley was wider but it works just fine with the smaller drive belt. It'll take some work. There are plenty of videos on how to do it. It's probably not as cold as the R12 because of the old style condenser but it works well enough.

[Fleetw00d]

I had several of mine, including Ruby, converted by a repair shop years ago; I don't think they changed any components, except maybe the drier. Ruby still works fine with an occasional addition of R134.

[chipocb7]

You usually just need to R134a fittings, flush the whole a/c system, and replace the receiver/dryer because it holds some oil plus the stuff inside absorbs the oil.

[Raf99]

You usually just need to R134a fittings, flush the whole a/c system, and replace the receiver/dryer because it holds some oil plus the stuff inside absorbs the oil.

This. I agree with Deev but I've heard nothing bad from people who changed the fittings and stuffed R134a in there. Depends how much you love your car I guess.

[The G-Man]

I put R-134A in my Accord back in the day... 2008-2009ish, luckily I have an uncle with the major AC tools. He pulled a vacuum on the system for a good while to get everything out and then we charged it with 134A. It blew cold until I stopped driving the thing late 2012. Yes the compressor/system isn't designed for 134A, but it will cool your car. I'd bet if you went as far as putting in a new compressor designed for 134 you'd be in a better boat. I can't imagine anything catastrophic happening to the rest of the system as long as you get as much of the R-12 out as possible.

[chipocb7]

Besides the r134a, is the oil used it creates acidity that can cause a catastrophic failure. Basically oil used on r12 and 134a is different. Its cheap to flush the system and replace the dryer/filter. Compressor dont "need" to be changed.

[NotMyGrandpas]

From what I understand as long as the compressor ran r 12 it is capable to run r 134a (correct me if I'm wrong) HOWEVER. you need need need to get the system cleaned/flushed first, then you can swap over the fittings for the high line and low line, and vacuum and recharge.

It's also best to get a new receiver dryer and "o" rings for everything...because if its still r12 it's more than likely not to have seen the light of day in the last 15 years..... so while you're in there just do it and save the headache.

I believe new dryers from rockauto are like $70 and you can get conversion fittings anywhere really for pretty cheap, just don't go too cheap