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by Richard Swenson
(Wareham, MA USA)
I am new to compressors. I just purchased a used 30 gallon/5.5 hp compressor (craftsman compressor 919.165310). It is working fine, but I notice that it will lose all it’s pressure if shutoff and left alone for about 2 days.

Is this normal? obviously there is a very small leak(s), but i don’t know if this should be expected or something i should address.
Any input would be greatly appreciated. Thanks.
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Compressor hold it’s pressure
In theory, once the compressed air gets to the tank, it should remain in the tank indefinitely.
The reality is that the tank check valve may leak a bit, a fitting on the discharge line may leak a bit, if the hose is plugged into the discharge coupler and whatever it’s attached too leaks a bit, over time, the tank pressure will dissipate.
That yours loses all air pressure in two days suggests a bit more than a small leak, and with the tank empty of air and the power off, I would pull the tank check valve and check it / clean it to see if that resolved the leak.
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Thanks…
Thank you for the help. i found the leak, and the system is holding pressure well now. thanks again.
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