a/c pressostat??

ccb222 · Post by **ccb222** » 22 Jul 2007, 09:45

Re: my post of Jul 20, 2007 about a/c/ relay, THANKS for the input--Another Q is: Somewhere I read about a/c "pressostat". Anybody know what this is, where it is, what it does, could it be my problem? My blower fan works fine always, just that the a/c unit intermittently stops producing cool air. As I said, I turn it off for 5 minutes or so and it works again just fine. BUT, now even that doesn't work EXCEPT when car is started first time of the day. Any more helpful suggestions? Thanks to all, ccb222

Post by **Ozark Lee** » 22 Jul 2007, 09:59

The A/C pressostat is an air pressure switch, it is desinged to kill the system if the pressure falls below minimum specification so as to save the compressor. It is located on the low pressure line just in front of the firewall. If your system works fine some/most of the time then it is fine.

Sounds like an A/C compressor clutch shimming in your future. There are a whole gob of threads over the last week or so with some good links. Here is a decent writeup (Check the PDF from N8-50) on how to do the job.

http://volvospeed.com/vs_forum/Ac-Therm ... 76833.html

...Lee

TheSwede · Post by **TheSwede** » 23 Jul 2007, 18:44

Your A/C is doing exactly what mine was doing. I could shut it off for a few minutes and but a few moments of precious A/C but those minutes got longer and longer as the clutch would wear. It finally got to the point where it would only work the first part of the day. I did the clutch shim referenced by Ozark Lee above and it worked like a charm. It only took about 20 minutes (with help and good tools) and was completely free. Try it out.