I just recently got a 95 850 Turbo. Everything is running fine except the AC, sometimes.

When it is really hot outside (Above 90) and Im running the AC, the cold air will stop blowing after about 5 minutes, and will just blow warm air. Then if i turn the AC off for about 1 minute, and turn it back on, cold air will come back out. I have read on another forum that someone with a V70 was having similar problems. He found out that his compressor clutch magnetic coil was overheating and cutting out. I do not know yet if the Evaporator has been replaced on this, but i intend to find out soon.

What makes me think its the same thing, is when its not so hot outside (in the 80s) the AC will blow non stop, and MUCH colder than when its hot out. It will never cut out.

Another thing ive noticed is that when i drive on trips (over 2 hours) with the AC on, a mist, or water vapor will come out of the vents. But it has yet to do it in the city.

So does it sound like the Compressor clutch coil? or maybe something else? Any help is appreciated. Thanks

I had the same problem with my 1999 S70 T5M where the a/c would cut off if outside temp. was over 90 degrees F. My Volvo dealer replaced all the sensors to no avail. The hi-temp heat sensor in the compressor was the problem. They told me the only fix is to replace the compressor, $800. There are not that many days over 90 degrees in Cleveland so I decided to live with it.

Hey Mike. I too am in Cleveland. Who are you using for service on your car?
I am totally discusted with the arrogance of both Leiken and Motor Cars.
The guys at Swedish Solutions are getting to the point that they tell you what you have to have done, or telly you to take it somewhere else.

Your thoughts please.

Joel
steellight@aol.com

Nalek,

I would not bypass any of the high pressure / overheat swtiches on the A/C system. They were put there by Volvo for a good reason: to protect your compressor when the lines are under unusual pressure, and to safeguard proper operation of the system. I had exactly the same problem you mentioned on my 1996 960 in the end of June this summer. I bought a pressure gauge and looked at the pressure in the A/C lines. Sure as heck, it was low on R134a. Started charging it, and it has been running wonderfully. FYI, R134a gauges & refrigerant is readily available at all car parts stores. In mine I used the Interdynamics R134a that contained R134a , 2 ounes of oil, and a Stop-leak all in one container. The car has a slow leak, and needs to be recharged every other year or so since new.

Good luck!

Azeez

Azeez,

Planning on the same approach. Can find the high side couping but have not yet found the low side coupling. Bought a Haynes book to find it that turned out to be useless. Am told that the coupling can be reached from under the car. Any ideas.

Thanks,

DC

I had the same problem with my 95T. I bypass the hi temp switch from the back of the compressor and it's been running great after that. Give me your email address if you guys want a drawing.

Aaron

Aaron,
Could you send me a drawing please?
daveshear@aol.com

Thanks so much!
David

Im not exactly sure what the High temp switch is, but I assume it has something to do with cutting off the compressor if it gets to hot? Correct me if thats wrong. But if thats right, wouldnt you want that so the compressor doesnt overheat? I had a friend with an acura and the compressor overheated and melted some bearings. But im always open for ideas, So if you want to send me some drawings, maybe an explaination of what exactly bypassing that switch does, id appreciate it. krathbun@iastate.edu

Thanks

Soory about the blank post - seem unable to log in.

Anyway......

There are some common things to check. As you mention there is a high temperature cutout on the compressor which in many hot countries is often disabled to prevent false operation.

Secondly, in high temperatures it is possible for the internal pressure to rise too high - this will cause the high pressure switch to oprate and close the system down until it recovers. An overcharge of refrigerant can cause freezing of the evaporator, causing blockage in the system. The low pressure switch will operate to cut off the compressor until the system recovers. Was your car topped up with R134 recently?

Good luck

KP

I had the dye added to mine and the leak showed up at the condenser and or accumulator. They didn't even look to see where the leak was coming from exactly, they just want to order and replace the parts. Has anyone out there ever had to replace the condenser and accumulator?
Thanks in advance.
Ian ( Nova Scotia Canada.)

yes i replaced both but not due to failure, i had a slight front end accident.

I paid about 139.00 for the condensor and i foreget how much the accumulater is (do you mean reciever/dryer) i think it was about 50.00

I used the recharge kit from wal mart and have not had a problem since that was around April.

you can get the parts for cheap and do it yourself and save the money on labor.
OR you can always change the parts yourself and have it evac/recharged at a shop.

I am sure i saved hundreds in labor charges.

I got my parts from John at Volvo parts independant (VPI) 713-722-0505

Hope this helps.

Dan

You should begin by having the AC system properly recovered, recharged with dye added before assuming anything more.
I have yet to see a bad compressor clutch in any 850.
THE most common AC problem with 850s is lack of freon and once properly charged, most problems are solved until the charge runs low again. If AC dye was previously added (dye sticker under hood) and it's low, someone should then be able to spot the source of the leak.