air conditioning nightmare!! - BMW Forum

jfertita · 06-05-2007, 10:36 AM

My a/c has been a nightmare since i purchased the car, i cant seem to get it to cool! over the past year i've replaced the receiver drier, evaporator, and evap expasion valve and gone through bottles of R-134a (conversion kit)..I took it to a shop and had it professionally evacuated and filled. He said that the compressor is weak and is not pumping the freon like it should so its not as cold.

Since the compressor is around 400 dollars is there anything else i should try before going ahead and replacing that? What do the switches on the receiver drier do? I wonder if they have a part in the problem..

Thanks for any help

Starmavin · 06-06-2007, 12:51 AM

Before you point your finger at your compressor as the problem (although in your case, it seems very plausible) make sure your recirculation system is working correctly. Remove your blower motor cover and have someone push the recirculation button. (the one below the A/C button) When pushed the 2 stage air valves should close on both sides. If one or none close your A/C max out put will be compromised. It is very common to have the articulator arm to break from the air valve flap, (pain in the ASS to fix) or the motor to break free from it's mount.

Also make sure your evaporator and condenser is clean and free of debris.

P.S. A while back I built a bracket that mounts a V belt 134a compressor in place of the stock compressor, I could easily duplicate it if there was any demand for it. I originally had plans to sell the bracket, hose adapters, and condenser in what I called a "Super Kool" kit, but no body seemed interested at the time.

jfertita · 06-06-2007, 01:00 PM

Ok, I'll check out the blower motor and see whats up, thanks for the advice. Btw when my a/c is on my idle is more erratic than when the a/c is off..i know its supposed to rise a bit but it will idle at around 1100 rpm sometimes, is that just my TPS off adjustment?

jfertita · 06-06-2007, 01:48 PM

also i just thought of something..the compressor engages and i hear the click sound when i press the blue a/c button but i dont ever hear any more clicks after that..is it supposed to be engaged all the time? i thought compressors had a switch that engaged and disengaged them..

Starmavin · 06-06-2007, 05:33 PM

No, in the e30 it comes on and stays on.

jfertita · 06-06-2007, 10:25 PM

Oh i see, thank you. and i checked the recirculation switch and i couldnt find any problems so i might as well go ahead and change out the compressor and hope for the best!

Starmavin · 06-06-2007, 11:51 PM

You checked the switch? I said check the operation of the air doors....

jfertita · 06-07-2007, 10:37 AM

Yeah thats what i mean't sorry i wasn't clear on that one..

jfertita · 06-22-2007, 11:13 AM

alright..so far i've changed the receiver dryer/expansion valve twice, the evaporator, and compressor...the air still wont go below 60 degrees..im totally confused. any ideas??

Starmavin · 06-22-2007, 11:56 PM

The receiver/drier and expansion valve are two different parts. The receiver/drier is the tank located below your washer fluid tank, the expansion block is located under the dash above the glove box. Explain in detail how you are charging system, what you are charging with, and how much you are using to charge. The oil you are using and how much.

jfertita · 06-23-2007, 10:48 AM

yeah im sorry i didnt mean to put the two together like that, i took it to a shop and had it vaccumed down and i charged it myself with 2 18 oz cans of R-134a with oil and leak protectant already in the can, maybe 2 cans isn't enough?

Starmavin · 06-23-2007, 01:33 PM

Actually 2 cans is too much. When converting an R12 system you fill it with 134A to 80% of the R12 amount. Now, I have never seen a 134A can with oil in it, I only see oil in the oil charge cans. Too much oil can cause your problem. On your receiver/drier there is a viewing port. tell me what you see with your A/C on for at least 10 min.

jfertita · 06-24-2007, 12:18 AM

I read the back of the bottle and it has 15oz of refrigerant and 3oz of oil in each can. so i put in 30oz of R-134a and 6oz of oil. When I run the a/c and look in that port i see a light green fluid with hardly any bubbles flowing.

Starmavin · 06-24-2007, 08:05 PM

If you can see fluid in your receiver, your system is over filled with oil. The light green fluid is oil and U/V dye. You'll have to take out your receiver drier and empty it out and flush your evaporator. There'll be enough oil in your compressor alone.

If you followed the directions on your new compressor correctly, you should have put at least 8oz. in your compressor before installing it. With the 6oz. what went in with the 134a plus if there is dye in it, the shop most likely put that in with even more oil.

jfertita · 06-28-2007, 02:06 PM

Ok, so here is what i did today: I opened up the shrader valve on the low side to let all the freon out and a bunch of light green fluid game out with it, im going to assume that this is the oil? Then I took off the receiver/drier that had a small leak near the sensor and fixed that. Then I refilled it with 3 10oz cans of R-134a with no additives so it was just straight up freon. The temp of the air coming out of the vents now is about 58 degrees on full blast.
Should i expect any colder on a european car running R-134a? I heard that sometimes it doesnt work that well when its converted from R-12..