98 Grand Caravan A/C help
 

I need some help. I have a 98 grand caravan 3.8l and i'm having some a/c issues.
I replaced the front evaporator and the front expansion valve 2 weeks ago, leak tested, filled the unit properly. Ever since than I can hear the evaporator pressurizing when the compressor cycles on. It's worked perfectly, blows 40 degree vent temp. 1 week later the compressor siezed... I just kind of figured that with 290,000 km's on it that it was time for a new one. Actually the compressor didn't sieze. the clutch let go, so there was no system contamination. I replaced the compressor, with a brand new one, and the dryer, tested and filled it. Again it worked perfectly. I could still hear the pressurizing noise in the front evaporator. (Don't know about the rear).... NOW HERE'S THE BEST PART... today I leave work and the new compressor SIEZED.. Is this just crappy luck, or am I missing something????? any info would be greatly appreciated as I am going to replace the compressor tomorrow. I'm just a little bit unsure about the pressurizing noise. I'v talked to a few different techs and nobody is sure. the general answer is that it must be low on refridgerant. I can assure that is not the case.
Again any help would be great.....thanks