the ac works but the high side hose and valve gets extremely hot. What could be causing this?
Yes under full load the high side will run too hot to touch, but you need to have the pressures checked just to be sure you don't have a blockage in the high sides abality to cool as it goes through the front exchanger.
You need to clean condenser coil with hose and nozzle. Sounds like the fins on coil is clogged with dirt and bugs. Not enough air flow going though condenser coil.
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