Had my a/c in my 95 850 Turbo Wagon charged and checked for leaks earlier this summer. Refrigerant was low and the system was recharged with no signs of leaks. Now it seems like sometimes the system is super cold, the next minute it shuts down and the air gets warm and humid. Cycling the temp setting usually doesn't get the system to kick back on but sometimes if I either cycle the a/c switch on and off or put the recirculate switch on, the air will get cold again. As of late, it seems that even that may not work, but after I shut down the car and get back in later and restart, the system is cold again. Any ideas why this is happening? Just when I think the a/c is shot, it blows cold, then I think it is OK and it goes warm. Strange.....

Keith

Could be the compressor. Check it to see if it is working. Do you hear the clicking sound? Mine did that for a while until it just had warm air coming out all the time. We need an evaporator and had been recharging for a couple of years or so.

If the compressor is working then I was told it could be the controls (you know, where the AUT knobs are, there's a board in the casing that may be malfunctioning) in the cabin. In earlier models you could solder something in there and fix the problem. But not in our model. The whole part would need to be replaced and used ones are usually not available...the new part costs around 6 or $700.

Post what you find out. The expense of all this is scary.

I've been in FL. without A/C since April.
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'95 854T 120,000

mine did the same thing, took to volvo for dx and the compressor was shot, had it replaced works great now. no shut down no warm humid air. compressor with install at volvo was 950.00 worth every penny. kelly

Sounds like the evaporator is freezing over with moisture. The temp control only mixes in hot air near the outlet so it does not thaw out the evap. Turning off the A/C thaws the evap. I'm not sure about what exactly should prevent that evap from getting too cold on that car. With fan on medium speed and temp max low, air from center vents should not be too much below 40 deg F.

LarryP is most likley correct.What cycles the compressor on your car is the low pressure switch. It is located on an ac pipe on the right side of the engine compartment near the firewall. Next time it quits,pull over safely and pop the hood. If one of the pipes has ice all over it(not condensation)the evaporator is frozen up.

Mine does the same with a new Evaporator and 2 new cabin sensors. If the Evap is freezing up, then what do you do? It does seem like I get goofy things happening and I wonder about the Controls on the dash. Sometimes I get cold air when I have the A/C switch off. And sometimes I swear I hear little clicks going on, even when the fan is off but the A/C is in the on position. Really strange. But mostly my prorblem is what was described on this Post.

Marty