Why is it a compressor will not build pressure? The motor runs, the pump sounds like it’s running, but the air pressure in the tank either doesn’t rise at all, or rises to a pressure point and then the pressure stops rising, even though the compressor continues to run and run.
A compressor is a pump. That pump pulls in free air from the atmosphere and is supposed to drive it into the tank, and that increases pressure in the compressor tank.
Different styles of air compressors, reciprocating versus rotary screw form example, accomplish this with different methods, yet they pretty much all do the same thing, suck in air from around the room or through an outside air intake and drive that air into a tank.
What to check on an air compressor when the compressor will not build pressure?
The air compressor reed or flapper valves (also known as the intake and pressure valves, or suction & discharge valves) are a common cause of why an air compressor will not build pressure.
The image below shows the pump of a small air compressor, and the valves on this model.
If the compressor valves or gaskets are what the pump problem is, then it will be necessary to disassemble the pump to repair that problem.
Before you do that, there are other reasons why an air compressor will not build pressure. Pretty much all of them are found here.
Get some help with a compressor that will not build pressure!
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