Compressor Abnormally High Current

What does E42 mean?

The system has detected an abnormally high current draw by the compressor. This indicates an overload condition, potentially due to mechanical issues, excessively high head pressure, or an electrical fault within the compressor motor.

• Compressor drawing abnormally high current.
• Compressor internal winding fault.
• Mechanical issue within the compressor.
• Low voltage supply to the compressor.
• Overload condition on the compressor circuit.

Click steps to track your progress.

1. 1

   Measure compressor running current on all three phases using a clamp meter — compare to the motor nameplate FLA.

2. 2

   Measure discharge and suction pressures to check for high head pressure or liquid slugging.

3. 3

   Measure winding resistance of the compressor motor phases (U-V, V-W, U-W) and to ground using an ohmmeter.