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critical Honeywell
Error Code Room Temperature Changing Trend is Reversed with System Mode
A high-severity alarm indicating room temperature is moving in the opposite direction of the active system mode (heating mode but temperature decreasing or cooling mode but temperature increasing).
? What Causes This
HVAC equipment malfunction, control output failure, or external heat/cooling source.
✓ How to Fix It
- Verify HVAC equipment outputs are energized.
- Check system mode configuration.
- Verify sensors are reading correctly.
- Contact service personnel.
Source: page 119 of the official manual
From the manual
This error code appears in:
Honeywell Home Thermostat