Auto Air Conditioning & Heater Repair: AC compressor seize up on 1999 Dodge Caravan, dodge caravan, compressor assembly

Question
The AC Compressor on my 3.3 liter 1999 Dodge Caravan, seized up. The system was operating very well until it seized. I checked Low pressure side and found the pressure at 70 psi, normal pressure is 45-50 psi ( I check it every month in summer). The system was seized up until my wife accidently turned on AC while on the expressway, don't know why belts didn't break but the Compressor was now freed up. The clutch is working, all relays and fuses are ok, but system doesn't cool. Should I replace the Compressor assembly, or is there a fix for this problem. There was no change in pressure after turning on the system, the clutch kicked in and compressor pulley was turning,  low pressure stayed at 70 psi.

Answer
Michael,

 Assuming the refridgerant level is not over or under charged, the compressor is running and the low side pressure is 70psi you could really only have one of a few problems.  If the compressor actually was siezed due to deteriorantion and one application "broke it free" then something may be broken internally and the pumping section of it is not moving but the bearing adn hub are.  
 If the low side is 70psi, the compressor is working fine the only other thing it could be is the H valve on the evaporator inlet/outlet.  Sometimes the valve gets stuck and there is no restriction to flow.
 Do you have any high side readings? That would be helpful.

Wayne