E440 (Red ON, Green Blink, Yellow OFF) — Heating operation unavailable due to high outdoor temperature

What does E440 mean?

The outdoor unit's PCB LED displays E440 when heating operation is not available because the outdoor air temperature is over 30°C (86°F). This is a normal operational limit, not a fault.

• Outdoor ambient temperature exceeding the system's operational limit for heating mode

Click steps to track your progress.

1. 1

   No direct user action is required for the unit itself; this is an operational safeguard.

2. 2

   Wait for the outdoor temperature to drop below 30°C (86°F) to resume heating operation.

3. 3

   Ensure the outdoor unit has adequate ventilation and is not exposed to abnormal heat sources.