!!
critical Honeywell
Error Code Room Temperature Changing Trend is Reversed with System Mode
Room temperature is moving in the opposite direction of the system operating mode (e.g., heating but temperature dropping).
? What Causes This
Valve malfunction, fan failure, incorrect system mode, or sensor error.
✓ How to Fix It
- Verify system mode is correct for the season.
- Check heating/cooling valve operation.
- Verify fan is running.
- Check space temperature sensor for accuracy.
- Contact service if malfunction suspected.
Source: page 103 of the official manual
From the manual
This error code appears in:
Honeywell Set Home Thermostat