Volvo: A/C off and on problems, compressor clutch, dual climate

Question
Dear Jimmy - I have a question similar to one you answered but I need some more info - I have a US model but am in Bosnia and the Volvo garage here is terrible.  The car is a 99 V70 2.5 turbo with the dual climate control. My problem is similar to the one below - when very hot outside, the AC works for a while but then when in town or idling, it suddenly stops cooling. It keeps blowing.  Then, if I turn it off for a few minutes, and then back on, it cools for a few minutes, then stops.  When it is below 90 degrees or so outside, it does not stop at all.  I took it to the shop. The volvo shop (said that they) cleaned and recharged the system, but it did not help, so I went back.  They now say that it seems to be the electric spool for the electromagnetic belt on the AC compressor clutch and that I can't just repair the spool, need to get a whole new AC clutch.  However, this does not sound to me like it is the problem. If the clutch didn't work, how would I have cooling at 90 F and not at 98F?  Do you also suggest that I just have them bypass the Tstat?

This is the previous question you had answered that is related...
Question
I have a 1997 960 Volvo with an A/C problem. In hot weather the A/C compressor works for few minutes and then turns off. After about 10-15 minutes the compressor works again for few more minutes and then turns off. When it is working, it is working properly. I ran the car at night for 25 minutes and the compressor did not turn off, and was working properly. I ran the car during the day when it was hot and the compressor turned off after 10 minutes, and back on again for few minutes. The blower does not go on or off. Again the air it was blowing was not cold. I checked the Freon pressure and it is at 35psi. The condenser is clean. I had the car for a year and a half and nothing was done to the A/C, it was working great till few days ago. Everything looks original. Someone told me that it might be the Pressure Stats, what do you think? I am trying to do the work myself and would appreciate your help.

Answer
Hello Joe! I would evacuate and recharge the system with some fresh refrigernat. Then I would bypass the thermostat located on the a/c compressor. The T/stat will shut the compressor off when it gets too hot. I hope this info helps you.  

Answer
Hey Chris! It sounds like a faulty A/C compressor to me. After the compressor gets hot the electric windings in the clutch loose contact. You will need to replace the compressor. There is no thermostat on this model. The best way to tell is to check for power at the compressor after it cuts out. If there is power, the compressor is faulty. I hope this info helps.


Jimmy