My 2002 Volvo V70 has 150,000 miles, in great condition and well taken care of, always garaged too. The air conditioner is not blowing any cold air. The compressor works and cycles, I checked the interior thermometer in the vent and it looked good. Doesn't need ac coolant. The air conditioner was fixed only a few years ago which cost us about $700+.

I'd like to know what the problem is before bringing it in or spending $100 on AC re-charge and that does not turn out to be problem.
Does anyone have any idea what could possibly be wrong or what I can check?

 

If the compressor works correctly, and the vent temperature is OK, what's the problem?

 

What do you mean the interior thermometer on the vent looked good? Are you implying vent temps are cold? That would negate the reason for the posting I would think....

There's only one way to be certain that it doesn't need refrigerant...by recovering the existing charge and weighing how much you recovered...period. Everything else is an educated (hopefully) guess. BTW, if you DO have a leak, do not add A/C Pro or any other can of refrigerant containing "Leak Sealer" (aka, death kits). If you end up adding refrigerant, use only pure R134a (the cans that contain UV dye are OK as well).

The fact that it was "fixed" a couple years ago brings on more questions. Was it a catastrophic compressor failure that necessitated the repair? If so, was the system properly flushed of any metallic debris? Failure to do so is a VERY common reason for replacement compressors to be short lived. People tend to just replace the compressor without removing the shrapnel left behind by the old one, and it proceeds to tear up the new compressor.

If you want to self-diagnose, get an a/c gauge set (BTW, the high side port is recessed on these Volvos and may require an adapter), and post some low/high side pressure readings at some specified ambient temperatures, and what the vent temperatures are during that time...doors open, engine running at 1500 rpm. The fact that the compressor is apparently engaging rules out a few things, but beyond that there's not a whole lot of real data to go on at this point.

If you happen to have a knockoff (or real for that matter) VIDA unit, it can display the reading from the evaporator temperature sensor as well as the high side pressure sensor reading.