[rheavn]

Chester,
Sounds like your 12V compressor is suffering from lack of use. Using it will loosen it up, or at least it has mine. Your 12V compressor should come on around 30 psi and shut off about 55 psi. It does run for a shorter time because it is only filling the small air storage tank that is located in the right drive wheel well. The 12V compressor only services the low pressure air systems for your slide seals, air toilets, air dump valves, and air pocket doors. I would not advise raising the air pressure on the 12V compressor.

The 110V compressor fills all 10 air tanks on your coach, including the one in the right drive wheel well that the 12V compressor fills. It comes on at 80 psi and shuts off at 110 psi. It does run longer, but it is filling many more air systems and larger air tanks.

If you take the covers off the pressure switches you should see a label with the pressure switch specs.

Hope this is helpful............................