Applicable Systems
RTAC 200
Symptoms
Defrost fault. The defrost cycle is not operating correctly in heat pump mode.
Possible Causes
- Defrost sensor failure giving incorrect readings
- Defrost control board or relay fault
Troubleshooting Steps
- Step 1: Check the defrost sensor resistance and wiring
Sensor is faulty or wiring is damaged - Step 2: Verify the defrost relay operation
Relay is not energizing
How to Reset
To reset: Replace the sensor or relay, then reset the controller.
Source: Trane HVAC Service Manual, Trane Inc.
Category: HVAC Residential