Error 121 — Indoor unit temperature sensor error (Short or Open)

What does 121 mean?

The temperature sensor inside the indoor unit is either short-circuited or has an open connection. This prevents accurate temperature readings.

• Damaged temperature sensor
• Loose wiring to the temperature sensor
• Faulty sensor connection

Click steps to track your progress.

1. 1

   Check the wiring connections for the indoor unit's temperature sensor.

2. 2

   Inspect the temperature sensor itself for any physical damage.

3. 3

   Ensure the sensor is correctly attached to the pipe if applicable.

4. 4

   If the issue persists, the sensor may need replacement.