My ac hasn't worked in years and I've finally decided to fix it. I was going to convert to R134, but I have some questions. I bought a new hose, compressor, and accumulater. I was reading an ac repair manuel and it says that unless I use hoses and a compressor specifically for R134 it will all leak out quickly. The book says I will also need a new condenser to run R134. It says that it is okay to use hoses and a compressor that had R12 run through it since the R12 leaves a film on the inside of the hoses and compressor that prevents the R134 from leaking out. The compressor I got off ebay is a rebuilt R12 compressor and the hoses are factory air from Autozone. Could I use these hoses and compressor or will I have to get ones specifically for R134? I don't want to have to keep recharging my ac all the time. Thanks.

 

Go to advance auto, i work there .... theres a kit there called a retro fit kit .... it will rechrage yoiur ac and convert it over to r134 all for about 40 bucks .... well wrth the money

 

Bring your car to an ac shop and let them do it, the system needs to be vaccumed out before you can charge it again.

 

No disrespect to 85TA, but if he's talking about the cans with oil, freon all in one, I think those kits are just scams. (personal opinion)

Backyard A/C conversion is almost a crapshoot as to how well/long it works, but I think the following tips will increase your chances:

1. Replace accumulator. Their life span is only 4 years officialy
2. Use Ester oil. It is compatible with R12 and R134. 6oz ONLY!(amount very important)
3. Flush reused parts as well as possible.
4. Replace orifice tube. I've heard good things about the variable, but if short on cash, get a ford blue tube. Lookup an 85 thunderbird for this. If you find metal shavings/gooey black gunk on the old one, your compressor is shot. Period.
5. Vaccumm down the system before charging. Numerous things this does, all good.
6. Get something to measure both low and high side pressures. Should be about 35psi on low side and 2.2 X ambient temp on the high side.
7. A parallel flow condensor would help, although not completely neccesary. It'll require custom made lines(not as scary as it sounds).

John's on the right track, although if you take it to a shop, you might as well just refill with the R12. Less cost, and less headache than a shop-done conversion.

Hope this helps you out. Let us know what ya do and the results.

 

Is R12 what was originally used in the car? I have a 90 Formula that I want to do the same thing to. I thought that R12 was not available on the market anymore.

 

You can still buy R12 you just have to get it specially ordered or go to a mom and pop auto shop. Although I did read in someother post that u need a licence to get R12. I'm not sure if that is true or not.

 

In Michigan you need a special license, or at least thats what I ahve been told, If you know someone in the heating and cooling industry they can still get it, and you can still get it at many auto parts stores.

The down side is R12 will cost you more than simply replacing all of the parts for your R12 system and replacing it with R134a, a new accumilator, a new radiator, a new pump and new everything else.

134 does not work as well IMHO in an R12 system, BUT its about all we have.

John

 

there is an alternative refrigerant out there that is almost a direct drop in for the r12 that was originally in the third ge cars. It's called hot shot R114. Yes you do need a licence since the epa mandated that all ozone depleting refrigerents must be recovered. This goes for not must cars, but your home refrigerators which also used r12, home air conditioners which almost all still today use r22.

 

no disrespect taken at all ... you do get what you pay for but they are worth the money if its already got some freon in it but i didnt relize till just now he needed to get the r12 out first anyhow.... see you learn sumtin new every day

 

Most cars since the 80's came with hoses designed for R-134a if I recall correctly. It was in anticipation of the need to change. R-12 hoses can hold in R-134a as long as they have been used in an R-12 system like you mentioned, the oil is what coats the hoses. R-12 is not produced anywhere anymore so it will only become more expensive in the future. A retrofitted R-134a system is not as efficient as R-12 by design, it's just a sad fact of the chemistry. However it can still provide adequate cooling. DO NOT use any off beat mixutres, use R-12 or R-134a. Like mentioned above don't forget the orifice tube. I think whoever did mine (don't know when it was done) didn't change the orifice tube and it doesn't work so great.

 

I REALLY want to say that 1994 was the first year for R-134a in production passenger cars across the board. Not 100% sure on the exact year, but thats when I remember seeng alot of new cars getting it.

John

 

Thanks for the replies everyone. I am taking me car in Wednesday to an ac shop. I'll get the old R12 evacuated and the guy said he would look at everything for me. I'm going to do the work myself, but it will be nice to have a professionals opinion. I'll let you know how everything works out.

 

My 1992 still has the factory A/C system, and it's R12, so conversion didn't start until after then, at least in Camaros.

 

I tried 134 but my experience was so bad (and this was installed by a mechanic I respect) that I eventually went back to R12. The 134 just didn't cool.

JamesC

 

i dont t hink r134 was mandatory until 1994 or 95. but some cars were allready running it back in the 80's

 

Pep Boys is having a sale on conversion kits. Today is the last day. Regular price: $44.95. Sale price with a coupon: $24.95.

 

I took my car in this morning to an AC repair shop. All of my R12 was gone, so I'm going to convert to R134. My compressor still works, it just didn't have enough AC pressure to make it run. But I think I'm still going to replace the accumlator and orifice tube. I'll try to work on it tommorrow. If anyone thinks that I should replace anything else let me know.

 

In addition to what you are doing (which is part of an actual retrofit procedure, so good work there), also adjust the clutch cycle switch on the accumulator.. R-134a operates at different pressures than R12, so take the plug off of that switch and turn the screw in the center so that the compressor cut-off happens at 25PSI instead of like 30 or so for R12.. This will prevent the compressor from cycling too much.. Or you can buy a 134a clutch cycle switch with the screw already turned to the proper position..

 

I've finally finished my conversion and it works great. I'd recommend doing it to anyone, it is easy to do and worth it if your ac doesn't work. Thanks for all your help everyone.

 

Grey, what was the approximate cost to get this done at the AC shop?

 

I did all the work myself, except for recharging the AC. The only thing I changed was the orifice tube and accumulator. The orifice tube was $33 for the varible tube, but I was actually able to get it for $20. The accumulator was something like $20, but it may have been a little less, I can't remember. I also bought one of the conversion kits from Advance Auto. I can't remember the exact price, but they aren't that expensive. It comes with the new adapters for converting to 134 and some cans of 134.

I had the shop vacuum and flush my system and recharge it. My line pressures were not correct, and it turned out that my compressor switch on back of the accumulator was bad. I had them replace it for thirty dollars. It cost fifty dollars for the recharge, another fifty for labor and vacuuming and flushing the system, and the switch cost thirty. If everything is working fine on yours, you could probably get the system flushed and recharged for one hundred dollars or less. By replacing the components yourself, you'll save a lot of money.