Air conditioner woes - PeachParts Mercedes-Benz Forum

sassparilla_kid · #1 06-03-2012, 08:23 PM

Hey y'all, so I tried to re-charge my A/C today and for some reason the compressor isn't kicking on. Any ideas what might cause this??

The compressor is just a little over a year old so I don't think that it is the problem, so maybe something electrical or vacuum? Just wondering if there is anything in particular I should check out.

I really want to get cold air working in the car again this week, since the 103*F summer temps are here again (its supposed to cool down a little this week though) and as much as I like driving with the windows down, I want to be able to actually get cold again

tangofox007 · #2 06-03-2012, 09:02 PM

You might try jumping the low pressure cut-out switch on the receiver/drier.

engatwork · #3 06-03-2012, 09:09 PM

Typically, if you jump the switch and the compressor pulls in then it is an indication that it is low on freon.

Yak · #4 06-03-2012, 09:31 PM

Based on join date and post count - have you reviewed the switch settings and the temp wheel position?

MIN and the button in the middle pressed? Not the EC button, that turns off the compressor.

Any other symptoms or relevant info? The blower works? You have heat when called for? Fan speed changes OK? If not, have you checked the fuses, particularly #8 and #14?

vstech · #5 06-03-2012, 10:05 PM

Quote:

Originally Posted by sassparilla_kid

Hey y'all, so I tried to re-charge my A/C today and for some reason the compressor isn't kicking on. Any ideas what might cause this??

The compressor is just a little over a year old so I don't think that it is the problem, so maybe something electrical or vacuum? Just wondering if there is anything in particular I should check out.

I really want to get cold air working in the car again this week, since the 103*F summer temps are here again (its supposed to cool down a little this week though) and as much as I like driving with the windows down, I want to be able to actually get cold again

exactly how are you charging the system?
what refrigerant are you using?
what oil is in the system?
if the system is out of refrigerant, the compressor will not come on.
if you only have a single low pressure hose on the charging can, it's going to take a while to get the freon in.
you have to SLOWLY release gas into the system until the pressure rises up enough to engage the compressor. I DO NOT RECOMMEND JUMPING THE PRESSURE SWITCH, AS THIS WILL PULL COMPRESSOR INTO A VACUUM, and you can get air in the system this way.
the can will rapidly get very cold charging with a gas, have a bucket of warm water to dunk the can in to keep it warm.

sassparilla_kid · #6 06-03-2012, 10:28 PM

Hey so more background info on everything.
-Temp wheel is all the way on cold, blower setting is max fan, and I usually have the vent selector on the second from right button
-checked fuses, they all looked good, I even made the mistake of touching one and it was, well, a little warm lol
-blower works well, heat works (more heat at low speed than high speed though, no idea what that is about)
-no idea what oil is in the system
-I'm just using duracool to refill it, mostly because I'm a starving college student.

Another important thing
-I think it was about may of last year I got the whole a/c system redone. New compressor, new driers, new everything except condenser. After about a month I noticed it wasn't getting as cool in the car as it had been when I got it back from the place I took it, but I just wrote it off as being another 20*F warmer out than it had been. Then over the next 2 months it got progressively warmer and warmer until it wasn't blowing cool any more.

I would have taken the car back to the place and had them fix their mistake, but they already took about a week and a half longer to fix it than they had told me when I first took it over there, and when I called them up to say it stopped working they said to bring it in and it would be a week or so to get it going again so I told them hell no.

If I remember anything else I'll make sure to update

vstech · #7 06-03-2012, 11:03 PM

2nd button from the right is economy, no a/c...

sassparilla_kid · #8 06-04-2012, 12:13 AM

Quote:

Originally Posted by vstech

2nd button from the right is economy, no a/c...

My bad, meant 2nd from left, the one with two white triangles. I don't think I've ever used the economy button

engatwork · #9 06-04-2012, 07:30 AM

I suspect you have a freon leak based on the way it gradually went bad. I would try to get it back to the ppl that did the work last year. It sounds to me that it was leaking upon completion of their work. Shouldn't really be much to finding/fixing it unless it is in the evaporator.

What kind of car is it?

sassparilla_kid · #10 06-04-2012, 07:36 PM

Quote:

Originally Posted by engatwork

I suspect you have a freon leak based on the way it gradually went bad. I would try to get it back to the ppl that did the work last year. It sounds to me that it was leaking upon completion of their work. Shouldn't really be much to finding/fixing it unless it is in the evaporator.

What kind of car is it?

Its an '82 300D Turbo, and I don't have any plans to take it back there, not getting any more business from me ever. I'll buy all the stuff to find the leak myself before going back. They initially told me it would take 3 days to get everything done, and 2 and a half weeks later I finally got it, and in the meantime I was stuck driving a Saturn Vue

anghrist · #11 06-04-2012, 08:33 PM

Quote:

Originally Posted by sassparilla_kid

Its an '82 300D Turbo, and I don't have any plans to take it back there, not getting any more business from me ever. I'll buy all the stuff to find the leak myself before going back. They initially told me it would take 3 days to get everything done, and 2 and a half weeks later I finally got it, and in the meantime I was stuck driving a Saturn Vue

I understand your frustration. Keep in mind that most shops are not set up for dealing with these cars and don't keep the needed parts in stock. You can not even expect an MB dealership to keep enough replacement parts to turn these cars around in a day or two. If it's something 'special' like the A/C from an '82, then they will be waiting for at least 5 days to get parts shipped from Germany. Heck, I have to do this myself when I tackle jobs with these cars, I don't see how the shops will be that much different.

sassparilla_kid · #12 06-04-2012, 09:30 PM

Quote:

Originally Posted by anghrist

I understand your frustration. Keep in mind that most shops are not set up for dealing with these cars and don't keep the needed parts in stock. You can not even expect an MB dealership to keep enough replacement parts to turn these cars around in a day or two. If it's something 'special' like the A/C from an '82, then they will be waiting for at least 5 days to get parts shipped from Germany. Heck, I have to do this myself when I tackle jobs with these cars, I don't see how the shops will be that much different.

I get what you're saying too, but I forgot to mention that the shop was a European auto repair place, that specializes in older Mercedes and BMW's, and at least two of the guys working there drive diesel w123's. As for them getting the parts and everything, they were able to get everything within 2 or 3 days, but they kept saying they couldn't get stuff and saying things along those lines. About a week after I was supposed to have the car back I went over there since I was tired of calling, and finally got the truth out of them. They said they had gotten all the parts several days earlier, and that they hadn't gotten around to it yet because they had some other more important stuff they needed to get done on some other cars, but when I peeked in the shop everybody was just sitting around.

vstech · #13 06-04-2012, 09:45 PM

... when Jaybob brought me his 83 240D, to fix the a/c, he picked up everything at the local autoparts store... nothing had to be ordered. the BRAND NEW compressor was a next day thing from the warehouse...
unless they were changing the evaporator or something else rare and unique... they were feeding you a line.

anghrist · #14 06-05-2012, 12:35 AM

Quote:

Originally Posted by vstech

... when Jaybob brought me his 83 240D, to fix the a/c, he picked up everything at the local autoparts store... nothing had to be ordered. the BRAND NEW compressor was a next day thing from the warehouse...
unless they were changing the evaporator or something else rare and unique... they were feeding you a line.

I think both of our statements are correct. Most parts are next day. It's only the 'Germany-only' parts that really eat into the schedule for me. Old firewall grommets and such don't tend to be high stock items at the local drop-ship warehouses.