The thermostat powers on but does not call for heat even when the setpoint is higher than the room temperature.

Safety first: Most steps are configuration-only. Do not open wiring unless necessary.

Steps to restore a heat call:

• 1. Verify the operating mode:
  • On the thermostat or in the Fibaro app, ensure the mode is set to Heat and not Off or Cooling.
• 2. Check the setpoint and hysteresis:
  • Increase the setpoint at least 3–4°C above the displayed room temperature.
  • In advanced settings, verify that the hysteresis (difference between on and off) is not set excessively high.
• 3. Confirm sensor selection:
  • In the thermostat configuration, check whether control is based on the air sensor, floor sensor, or a combination.
  • If the floor sensor is selected but none is installed, the thermostat may inhibit heating.
• 4. Compare temperature readings:
  • Use an external thermometer to compare with the thermostat's reading.
  • If the thermostat reads much higher than the actual temperature, the sensor may be faulty.
• 5. Reset the configuration:
  • If misconfiguration is suspected, perform a factory reset and reconfigure basic parameters.

When to call a professional: If the thermostat appears to call for heat but the heating system still does not respond, an HVAC technician should check the downstream actuators and valves.