After around 20,000 hours or four years of operation, screw air compressors usually require major maintenance, including bearing replacement. Long-term operation leads to internal bearing wear, causing loud noise and high temperatures. These signs indicate the need for an overhaul.
[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] This manual describes the safety precautions, structure and functions of all systems and components, as well as the operation and maintenance methods for the KHE series rotary screw air compressors. The owner and operator shall read the manual carefully.
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