Error E7 / Indoor Red LED Flashes Once — Indoor return air sensor fault or heating overload

What does E7 / Indoor Red LED 1 flash mean?

Error E7, signaled by a single flash of the indoor unit's red LED, indicates a defective indoor return air sensor (ThIA) or a poor connection. It can also be triggered by an unusually high temperature in the indoor heat exchanger during heating, suggesting an overload.

• Indoor unit return sensor (ThIA) defective (open or closed circuit)
• Poor connection of sensor connector on the indoor PCB
• Overload in heating (extraordinarily high indoor heat exchanger temperature)

Click steps to track your progress.

1. 1

   Turn off the power to the air conditioner.

2. 2

   Check the connection of the indoor return air sensor (ThIA) to the indoor PCB, ensuring it's firm.

3. 3

   If the unit was in heating mode, try operating it in a different mode or at a lower setting after restarting.

4. 4

   Ensure indoor airflow is not obstructed by furniture or curtains.

5. 5

   If the error persists, contact a technician to inspect or replace the sensor.