There could be a couple of things wrong when your central pneumatic compressor refuses to build air pressure. It could be the pump gasket, failure of the pump piston, or it could be that air exits through the intake valve, If you are trying to troubleshoot the problem, here are some guides that can help you.
The reason why air pressure won?t build
The air compressor could be trying to build pressure, but it?s not possible because of a serious leak in the compressor. For a quick check, look at the valve on the tank drain. If the tank drain of the compressor is left open, ensure that you close the tank before starting the compressor. If not, the rate air drains out will be more than the rate it comes it. This will leave a major problem as the compressor may run but lacks any pressure. The solution? Change your pump and have it replace with another with the same model and make.
Other reasons
If you notice there is no major leak but air still leaks, albeit slightly, you can check any of the following.
Check the pump gasket
Gaskets are located at the upper side of your compressor with valve plates. The major function of the pump gasket is to make sure the incoming air is controlled within the lower region of the pump. Then the air moves through the pressure valve into the compressor tank.
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