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. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere.
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[pdf] Solutions: Inspect the system for leaks, replace clogged filters, and check for worn parts like seals or rotors. Possible Causes: Loose components, bearing wear, or improper alignment. Solutions: Tighten loose components, inspect bearings, and ensure proper alignment of moving parts.
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