What Does Error Code 71 Indicate?
Trane RTU Error Code 71 commonly indicates a discharge air temperature limit fault or high temperature protection event.
The unit has detected temperatures outside of safe operating range.
Common Causes
- Failed discharge air temperature sensor
- Blocked condenser coil
- Inadequate airflow
- Refrigerant overcharge
- Stuck economizer damper
- Faulty limit switch
Troubleshooting Steps
1. Inspect Condenser Coil
Dirty coils can cause excessive temperature buildup.
Clean if necessary.
2. Verify Sensor Accuracy
Measure sensor resistance and compare to manufacturer chart.
Replace if out of range.
3. Check Airflow
Confirm fan operation and unobstructed airflow paths.
4. Inspect Refrigerant Pressures
Overcharge or restriction can elevate discharge temperature.
FAQ
Is this related to high head pressure?
Often yes. High head pressure conditions can trigger temperature protection.