2000 volvo v70 air conditioning mystery

mechanic has tried two attempts at correcting the a/c -on/off cooling problem. Blows cold initially; then hot. He “removed the shim”. No luck. Then decided I needed new compressor. I felt that I did not; but authorized. Still have problem.

Any suggestions as to other causes would be appreciated. Thank you.

If the compressor is still running it may be a blend door or heat cutoff component problem. WAG as I do not know volvos.

I had a similar problem with a Ford Aerostar years ago. The mechanic figured it out by hooking his gauges to the AC system. When the air conditioning started blowing warm air, he looked at the gauges and the readings were too high. He directed the air flow from his shop fan through the radiator. The readings dropped and then the system started blowing cold air. In my case, the fan clutch was not allowing the fan to spin fast enough to pull air through the AC condenser. I don’t know what kind of fan set up a Volvo has, but if the fan isn’t pulling enough air through the condenser, this can cause the problem.

Thank you for the comments. I am writing down to take to mechanic tomorrow. I would love to hear other ideas, if anyone out there is in the know.