Page 322 - Reciprocating Compressors Operation Maintenance

Troubleshooting Compressor Problems 3O7

A knock in the compressor running gear is most frequently caused by a
loose part or a bearing that has too much clearance.

Squealing Noise

Possible causes of squealing noise in compressors include the following:

1. Motor or compressor bearing too tight
2, Lack of oil
3, Belts slipping
4. Leaking gasket or joint

FAILURE TO RUN

If the machine continually blows fuses, the following should be
checked:

1. Fuses too small
2. Voltage is low
3. Pressure switch differential is set too close
4. Compressor does not unload for starting
5. Motor bearings are beginning to seize

Should the motor fail to even start upon demand, the following points
should be checked:

1. Pressure switch contacts not mating
2. Worn contacts
3. Motor seized
4. Thermal overloads require resetting
5. Fuses blown

For possible solutions to typical problems, check Troubleshooting Chart,
Table 5-1. Always be sure to study and consult the compressor instruction
book. And DO NOT FORGET TO CHECK THE PRESSURE GAUGES.

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