Applicable Systems
Copeland Scroll Compressor (CoreSense/Comfort Alert)
Symptoms
The compressor trips on motor overload. The motor current has exceeded the rated value for an extended period, activating the overload protection.
Possible Causes
- Compressor running outside design conditions with excessive load
- Low supply voltage causing high motor current
- Shorted motor windings or partial ground fault
Troubleshooting Steps
- Step 1: Check motor current with a clamp meter and compare to nameplate FLA
Current is at or below the nameplate full load amps - Step 2: Verify supply voltage at the compressor terminals under load
Voltage is within 10 percent of rated value - Step 3: Megger test the motor windings for insulation integrity
Insulation resistance exceeds 100 megohms
How to Reset
To reset: Clear the overload condition, allow the motor to cool, then press the overload reset button.
Source: Copeland Scroll Compressor Service Manual, Emerson Climate Technologies
Category: Refrigeration