Red 3 Flashes, Green 7 Flashes (Single System) — Heatsink Sensor Error

What does Red 3 Flashes, Green 7 Flashes mean?

The red LED flashes three times and the green LED flashes seven times on the indoor unit. This indicates an error with the heatsink temperature sensor, typically located in the outdoor unit's inverter section.

• Faulty heatsink sensor or its wiring.
• Overheating of the inverter due to restricted airflow.
• Problem with the outdoor unit's power inverter module.

Click steps to track your progress.

1. 1

   Turn off the air conditioner system at the main circuit breaker.

2. 2

   Ensure the outdoor unit is free of obstructions that could block airflow to the heatsink.

3. 3

   Wait a few minutes, then restore power to the system.

4. 4

   If the error reappears, professional service is needed to inspect the inverter and sensor.