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] It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running.
[pdf] Check whether the oil content in the condensate discharged from the drain valve of the Kaishan air compressor is too high, whether the oil level of the compressor is too high, whether the opening pressure of the small pressure valve is normal, whether the return oil pipe is blocked, and whether the oil separation core is blocked.
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