Originally Posted by scott

Still haven't solved the problem. I've replaced the pressure relief valve; I have purged the system and replaced the freon; I removed the grill and cleaned the condenser. The compressor comes on as it should. Checking pressure the low side pressure is 120, the high side is 400. After running for approximately 2-3 minutes the compressor shuts off.

Can you guys think of anything else I should try?