Code 55 — Coil Temp Sensor Fault

What does 55 mean?

This fault indicates a problem with the coil temperature sensor, affecting Infinity/Evolution ODU Two Capacity, 18VS,19VS/V-HP/AC, Greenspeed/Extreme, and Infinity/Evolution ODU Single Capacity units. The system cannot accurately monitor coil temperatures.

• Faulty coil temperature sensor
• Damaged or loose wiring to the sensor
• Sensor disconnected or shorted
• Control board unable to read sensor data

Click steps to track your progress.

1. 1

   Check and replace dirty air filters in the indoor unit to ensure proper airflow.

2. 2

   Turn off the power to the system at the circuit breaker for 30 seconds, then restore.

3. 3

   Ensure the indoor coil area is free from ice buildup (if applicable).

4. 4

   If the fault continues, contact a qualified HVAC technician to inspect or replace the coil sensor.