I'm down about a pound of R12 and my AC is very anemic. But my body shop who did my repairs doesn't have the equipment to flush the R12 and replace it with R34 plus adapter. So he recommends that I find someone with a dedicated R12 vacuum system (very hard to find I'd guess) or just find some more R12. He had no idea where to find it these days. Where do you guys get yours when you need it?
Any automotive shop equipped to handle air conditioning work should handle that. I should caution you though, R12 is getting harder and harder to find, and more expensive too. It's more than $50 a pound wholesale though. Probably close to $75 to $100 or more per pound retail though. Also, as long as your car has R12 or R134a and not one of those substitutes in your system you should be OK. If you've got one of those freon substitutes in your system though, God help you, because almost no service shop will touch you for fear of contaminating their freon evacuation equipment You may want to consider if you want to continue supporting such an increasingly expensive R12 system, or convert to R134a. Each has its tradeoffs. R12 will give you slightly better cooling performance and retain stock cooling ability, at an increasingly escalating cost, since R12 is gradually being phased out. Or you can trade a little cooling performance and keep some of your money in your wallet by upgrading your system to the more environmentally friendly R-134a. That's up to you though. Good luck!
Thanks, bcweir. I was told that a shop can't withdraw the R12 with a vacuuming system that uses R134a because you're not supposed to mix the two and contaminate the system with R12. He said that I'd need to find a shop that has a dedicated R12 system to remove the R12, then he could attach an adapter to the condenser and put in the R134a. Is this correct? But I will check out the local AC shops and see what they can do for me. At this point I'd rather do the conversion to R134a.
I did the 134 conversion on our '85 325e and was not happy with the results. I changed the evaporator, receiver/dryer, O-rings, and oil along with the 134. It didn't cool nearly as well as 12. I was told I should also change the condenser to improve the cooling. Wasn't worth the cost to me. We went through this last spring on mye28.com and some were finding tanks of 12 on craigslist.
The shop is correct. R12 and R134a should never be mixed, as each would contaminate the other. What the shop told you was spot-on. R12 service is getting harder and harder to find. You may find yourself resigned to either some extensive detective work finding a shop, or converting to R-134a. I should point out that R-134a has slightly less cooling performance than R12. Some, like "John in VA" are able to tell the difference right away. To others, it's a minor difference. I think it's a judgement call and a matter of what you're willing to pay for. The one thing I CAN tell you for certain is that R12 is NOT getting any easier to find or service.
I had a conversation in the last month or so with someone whose business is all kinds of refrigeration services; I think I recall him mentioning wholesale r12 prices had dropped some from what I thought they had been (similar to prices bcweir points out); also, that r12 is readily available for those certified to work with it. Since the demand is going to be so much less and only for much older cars now, I think that's why it's more difficult to find shops offering the service. Here, we are fortunate to have at least a couple of long-established indy shops w/ BMW's as a mainstay and they have the r12 machines. I'd say start the search w/ indy shops specializing in BMW's or european cars in your area. As to how well r134 works in a r12 system, that's going to depend on your sensitivity to hot/cold, and need for cooling in your car. If you're in someplace where it gets hot, or hot and muggy, you probably want the max cooling you can get, unless you're someone who's physically comfortable in hotter temps. There's no question r12 will be more expensive to keep in the car, and if you can find a shop that offers it, it'll be up to you if you want to pay for it. Make some calls, or ask your chapter officers or other club members, you might be able to find someplace with some digging. Just because it's not the 'freon-du-jour' doesn't mean it will be impossible to find!
Important! DO NOT put R134a in a R12 system or vice versa. Some R12 compressors can be adapted to work with R134a by changing the seals, fittings and a few other parts inside it. But R134a should never be introduced directly into an R12 system or vice versa. The two refrigerants are not compatible. R134a molecules are much smaller than R12 molecules, and R12 rubber compressor seals will be damaged by R134a. The result will be a damaged air conditioning system and a mess you do not want to have to pay for and clean up. Also, make sure that the a/c technician is certified to work with R12. Not only is it illegal to purchase or sell R12 "over the counter" without this certification, but it's also illegal to improperly discharge an R12 system into the atmosphere (it's a federal violation).
I live in Massachusetts and I don't really need hi-test AC, or only on rare occasions, so that speaks in favor of doing the 134 conversion. But the glitch seems to me to be that, even to convert to 134 I have to find a shop that has a dedicated R12 vacuum (or whatever it's called) even just to remove the current R12 from the cooling system, since the two types of coolant can not ever be mixed. So my search will be for a shop that has a dedicated R12 removal system, and then I can have installed the adapter pieces for changing over to 134. I will start out by talking with the indie BMW guys I know around here.
Steve seemed to understand what I meant, but perhaps it would have been clearer to say "how well r134 works in a system originally engineered for r12, AFTER a PROPERLY DONE conversion." I was not suggesting just dumping r134 into a r12 system, but rather trying to mention additional points one might take into consideration when deliberating over whether to stick with r12 or opt for r134.
Found it! An R12 to R134a conversion done on an E32 http://bmwe32.masscom.net/johan/aircon_R134a/aircon_R134a.html
When it's your wife and children that are complaining that it's too hot, you have to make the right move!
Beautiful, thanks bc! The crux of the problem comes in this quote from your linked article: "You can unbolt the compressor and pour out the old oil or have a shop flush the system with R12 to remove the old oil." I'm not so sure that merely pouring out the R12 would be sufficient, because it's my understanding that ALL of it has to be effectively removed from the coolant system. I'm repeating myself here, but I need to find a shop that has a coolant evacuator system dedicated to R12...that is getting harder and harder to find these days. I will get on the phone this week and keep folks apprised of my progress.
Late to the party here. But stick with the R12 if you can. Find a shop who handles it (ask around somebody will know somebody who does it), in the long run it will be simpler and you will probably be happier on that 90+ degree day that you will get this summer. Don't forget your car is black!
Just keep in mind that article mainly deals with an E32 - your system may vary Regardless of the method, the goal is the same - to make sure that there is no R12 left in your system. The E32 7-series (1988 to 1994) is quite similar mechanically to the E34 5-series (1989 to 1996). It's meant to be a basic guide to converting an R12 system over to R-134a. There may be differences to your system, but I think the article gets the important parts correct. You're welcome, good luck, and let us know how it goes for you!
Or, you could just suck it up like the rest of us E30 owners with non-working AC and stick it out with the front windows open, rear pop-out windows popped open, and sunroof all the way back.
That may not be the best for certain situations I don't recommend cooling the car's interior this way while it's raining -- and it does rain in the summer too. Cars that live in far northern climates probably won't notice the difference between R12 and R-134a cooling performance. However cars in the southern climates would likely exhibit the several more minutes it takes to cool down a 100-degree+plus dark interior with R134a. To each their own. Your experience may vary!
Relative to the cost of changing a bunch of hardware, the price of a couple of pounds of R12 is comparatively cheap. A critical issue is whether the system is leaking. If it is, then hardware changes may mean that concurrent conversion is worthwhile. I just recharged my 325ic last summer with R12 after it had leaked down over a 12 year period. Hoping for the best.
