If the capacity of the air compressor is really too low, check the following: Check differential pressure over oil separator. Replace separator when necessary. Check and replace compressed air filters (if installed). Compressor does not unload. Check if pressure switch is correctly set and working.
[pdf] This test is performed to ensure that there are no leaks in the piping, compressor, or other pressure containing parts of the package. All openings in the completed compressor package are plugged and the unit is pressurized with nitrogen to 350 psig.
[pdf] Adding back pressure will reduce over compression by maintaining the internal discharge pressure throughout the entirety of the discharge port. Essentially, vibrations within the compressor are reduced by forcing rapid expansion to occur in the discharge line instead of the discharge port.
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