Dixell/Copeland AL10

What does Dixell/Copeland AL10 mean?

The AL10 alarm on the Dixell IC100CX iChill controller indicates compressor thermal protection has activated. The controller tracks the number of thermal protection events per hour; when that count exceeds the configured limit (defined by parameter AL14+AL15 logic), the alarm escalates to a manual reset condition. Until manually reset from the function menu, the compressor remains locked out.

Symptoms

• AL10 displayed on the IC100CX controller screen.
• Affected compressor stops and does not restart automatically.
• Alarm icon lit and buzzer active.
• Multiple compressor thermal trips logged in the alarm history within a short interval.

Common causes

• Compressor overheating due to inadequate cooling or ventilation.
• High return gas temperature from low refrigerant charge.
• Compressor running in excessive ambient heat beyond design rating.
• Internal compressor winding fault causing repeated thermal cutouts.
• High compression ratio due to low suction or high discharge pressure stressing the motor.

Diagnostic steps

1. 01

   Review alarm event history

   Access the alarm log on the IC100CX to count how many thermal events occurred within the hour. A high count over a short window confirms repeated compressor thermal trips.

2. 02

   Check compressor discharge temperature

   Measure compressor discharge line temperature or check the discharge temperature probe reading. Temperatures above 120°C (248°F) on the discharge line indicate excessive compression ratio or low refrigerant.

3. 03

   Inspect compressor cooling

   Verify compressor cooling fan (if fitted) is running and compressor body is not obstructed from airflow. Clean any dirt from the compressor shell and motor casing.

4. 04

   Check suction superheat and operating pressures

   Connect gauges and measure suction and discharge pressure. Low suction with high discharge pressure indicates a refrigerant-side problem stressing the compressor motor thermally.

5. 05

   Perform manual reset

   After resolving the root cause, navigate to AlrM in the IC100CX function menu, select AL10, and press SET to execute the manual reset. The compressor will not restart without this step.

When to call a professional

A licensed refrigeration technician should be engaged if the compressor continues to trip thermally after operating conditions are corrected, if winding insulation testing (megohm testing) is needed to assess internal compressor health, or if refrigerant system adjustments are required to bring compression ratio within safe limits.