AC issue on the wifes suburban

[THEFERMANATOR]

Originally Posted by Destroyer

I may just be stating something that you already know, but slugging a compressor is when you introduce a "slug" of liquid refrigerant into the compressor itself. Since liquid is not compressible, it causes the compressor to lock up. If the compressor is locked, then the belt will usually either fly off or break. Sounds like that is what the book is talking about. Eventually the liquid will usually turn back into gas, and the compressor will return to proper operation, making it look like the problem was someplace else. An overfilled system is usually the cause of slugging, but I have seen cases where the air passages in the evap coil are so clogged with hair or leaves that the the hot liquid cannot completely boil off in the evap coil and so it returns as liquid back to the compressor.

The problem seems to follow dual A/C units and GM's idea of not routing the low side line from the rear evap into the accumulator before the compressor. For some reason GM ran the rear air return straight to the compressor which is where the problem stems from. ALOT of compressors from 92-95 were lost because of liquid getting returned to the compressor and slugging it before GM came out with a revised expansion valve for the rear A/C unit. The big problem comes into play with people not turning on the rear A/C units fan, this is what allows the most liquid to hit the compressor.