Room temperature never reaches the setpoint even though the thermostat shows a heating demand.

Safety first: No special hazards; avoid moving wiring unless power is isolated.

• Check setpoint and schedule: Ensure the programmed schedule actually raises the setpoint to the desired temperature at the correct times. Disable eco or setback modes temporarily.
• Verify boiler temperature: On the boiler, check that the CH flow temperature is not set too low (e.g., below 55°C on non-low-temperature systems).
• Assess thermostat location: If the thermostat is in a cold hallway or near a draughty door, it may shut off heating before other rooms are warm. Consider relocating the thermostat to a representative living area or using a Vokera remote room sensor if supported.
• Check radiators: Ensure radiators in the main rooms are fully bled and valves are open. Balance the system if some rooms heat much faster than others.
• If the problem persists: You may need zoning or additional controls. Consult a heating engineer for system design improvements.