Effectively Handling Compressor and Electrical Motor Problems


Air compressors from time to time will encounter problems which is why you need to visit an air compressor repair shop. The key in diagnosing any problem during your air compressor repair in Toronto is with the use of a good digital multimeter (DMM). The DMM can be used in reading suction as well as discharge pressure, overnight temperatures, discharge line temperatures and valve performance. The clamp meter on the other hand is an excellent tool used in troubleshooting electrical motor as well as compressor problems. The meters which are designed in order to accurately measure both AC current and AC voltage are especially very useful. They will allow you to measure current without the need to break into the electrical circuit.

Compressor Electricals

In order to check the air compressor for electrical problems during your air compressor repair in Toronto, you can remove first the electrical terminal cover and then check the following external connections of the equipment.

  • Check the line voltage near the load center with the compressor off. The low line voltage will cause the motor to draw more current compared to the normal and may result in overheating as well as in premature failure. The line voltage which is too high will also cause excessive inrush current at the motor start and will again lead to premature failure.
  • Also check the line voltage at the motor terminals while the compressor is running. The voltage should be within the 10 percent of the motor rating.
  • Check the running current. The readings on it should be exceeding the full load rated amps of the manufacturers during heavy load periods. The low amps are normal typically during low-load conditions. Excessive high current can also be due to the grounded or shorted windings, a bad capacitor, and a faulty in the relay or an indication that there is already excessive bearing fatigue.

You are to be warned that when you perform air compressor repair in Toronto with internal thermal motor protection devices which have been running extremely hot, you need to ensure to give the air compressor some time in order to cool down before the electrical test. This will then allow the device to reset back to its normal position.

Failures in Motor Caused by Refrigeration System

There are times wherein a service technician might misdiagnose what is usually a defective compressor with electrical winding failures as one that is caused by an electrical system problem. The true cause of compressor electrical problems is often mechanical system failure and even inferior installation as well as service practices. The problems will include the following:

  • Poor piping practices which result in oil not really returning to the compressor after the run cycle.
  • The high discharge temperatures creates acid in the oil.
  • Insufficient airflow across the condenser and evaporator coils.
  • There is an extremely low suction pressure.
  • Liquid refrigerant flood back into the compressor.

If you encounter a problem with compressor bearing failure or a lockup you can actually attribute this to poor piping practices. This will lead to oil clogging in the system and will then result to insufficient oil return into the compressor.


By valariearthur

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s