Error E35 / Outdoor Red LED Flashes Once — Outdoor heat exchanger sensor fault or cooling high pressure

What does E35 / Outdoor Red LED 1 flash mean?

Error E35, signaled by a single flash of the outdoor unit's red LED, means the outdoor unit's heat exchanger sensor (ThOR) is defective (open or closed circuit), has a poor connection, or indicates excessively high pressure during cooling.

• Outdoor unit heat exchanger sensor (ThOR) defective (open circuit or closed circuit)
• Poor connection of sensor connector on the outdoor unit PCB
• Cooling high pressure

Click steps to track your progress.

1. 1

   Turn off the main power supply to the outdoor unit.

2. 2

   Locate the outdoor unit's heat exchanger sensor (ThOR) and inspect its connection to the PCB, ensuring it is firmly seated and free from corrosion or damage.

3. 3

   Check for any obstructions around the outdoor unit that might restrict airflow, such as debris or overgrown plants.

4. 4

   Ensure the outdoor coil is clean and free of dirt, which can cause high pressure.

5. 5

   If the issue persists, a professional technician should inspect refrigerant levels and system pressure.