AC Diagnostic Q's - Experts, please step inside
Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,518
Likes: 1,304
From: Windermere FL
AC Diagnostic Q's - Experts, please step inside
C4'ers -
It is hot here in Florida and my AC just cut out. I had converted it to R134 a year and a half ago and it was working perfectly - till now. Do not see the compressor enguaging.
Got it home and put a guage on it. Low side read over 200psi!!
I let some freon out of the low side (till it had about 60lbs with it not running) and the compressor still will not enguage.
Electronic controller had a code of '09' - low freon. I disco the battery to reset it. Start it up and compressor cycles. Guage goes from 20-60 lbs (compressor on to off). I try to add a can freon after disco battery again. Compressor cycles and guage reads 200 lbs again with can connected. Code sets again.
I assume there is some sort of blockage? Should I just remove the orifice tube to inspect it or might it have a block somewhere else?
Any diagostic tips would be appreciated.
It is hot here in Florida and my AC just cut out. I had converted it to R134 a year and a half ago and it was working perfectly - till now. Do not see the compressor enguaging.
Got it home and put a guage on it. Low side read over 200psi!!
I let some freon out of the low side (till it had about 60lbs with it not running) and the compressor still will not enguage.
Electronic controller had a code of '09' - low freon. I disco the battery to reset it. Start it up and compressor cycles. Guage goes from 20-60 lbs (compressor on to off). I try to add a can freon after disco battery again. Compressor cycles and guage reads 200 lbs again with can connected. Code sets again.
I assume there is some sort of blockage? Should I just remove the orifice tube to inspect it or might it have a block somewhere else?
Any diagostic tips would be appreciated.
Last edited by Flame Red; Sep 2, 2005 at 02:49 PM.
Racer
Joined: Jul 2005
Posts: 301
Likes: 0
From: Dallas/Spring Texas
The beauty of a/c systems is that they're all functionally the same. The pressure you see at any given time can vary with ambient temp but should be in the 20-40 psi range on the low side and 225-325 on the high side when running. The static pressure (after being allowed to equalize) should be in the 90-110 psi range on both sides. If there is a restriction anywhere then your low side will drop like a rock and possibly go into a vacuum and your high side will skyrocket and possibly blow the relief valve out on the compressor, unless the restriction happens to be between the low side diagnostic connection and the compressor and in that case I would think both pressures would be higher, but I've never actually seen that happen.
Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,518
Likes: 1,304
From: Windermere FL
Thanks - that is kind of what I expected to hear. I pulled the little valve thingy that goes into the pass compartment (forget what it is called). A couple of metal flakes. Nothing too excessive. I figured I had another one (spare) and I installed it. Now I put one can of R134 into it and it seems to behave normally. Have to get one more part of a can in there and should be good as new. I assume that little valve somehow got pluged?
