Alert Code 437 — Heat-sink temperature sensor fault

What does 437 mean?

The temperature sensor for the inverter's heat sink has failed, reporting extreme temperatures. This will cause the outdoor unit to stop. Repeated faults can lead to a system lockout.

• Heat sink temperature sensor failure
• Sensor reading outside of operating range

Click steps to track your progress.

1. 1

   Moderate fault conditions should clear automatically. Critical fault conditions require restarting the system by cycling power to the outdoor unit.

2. 2

   Ensure the outdoor unit is not exposed to extreme ambient temperatures that could cause sensor errors.