As some of you know, I have a 1969 Corvette that fell into my lap for a price I couldn't refuse, so I have made that a (near) daily driver. The car is a small block 350 car, with PS, PB, TH400 auto, power windows and factory A/C. I've been working to get everything working just like it should. The last thing needed is the A/C. These cars had a problematic A/C component called a POA valve. I replaced this with a POA replacement and did a huge amount of work replacing nearly everything as well as cleaning stuff (even though it was very clean inside). This replacement POA has a pressure switch that cycles the compressor ON at 42 PSI and off at 22 PSI.
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The switch doesn't turn the compressor off properly at the low pressure. 
It turns it off, then on, off, on, and continues cycling like this maybe 20-40 times before it finally "lets go" and turns off the compressor. It is beating the crap out of my compressor clutch. I have watched the pressures and everything else works like it should. If I manually activate the compressor while watching the pressures my A/C blows 42 degree air and works great.
But to fix this? First Old Air Products is telling me that even if I replace the switch (which requires removal of all Freon) it might still work poorly. So they are recommending I buy a separate thermal switch that's cost me around $55.
Why the he77 should I have to spend $55, plus all the hassle and Freon/ evacuation costs to fix something that THEY built and sold me but doesn't work??? Grrrrrr.....
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