Room is too cold even though Tado Smart Thermostat is calling for heat; boiler runs but radiators stay lukewarm.

Safety warning: Radiators and pipes can be hot. Allow them to cool before adjusting valves.

• Check setpoint: Ensure the room’s target temperature in the Tado app is higher than the current temperature by at least 1–2°C.
• Boiler flow temperature: On the boiler control panel, increase the central heating flow temperature within the manufacturer’s recommended range (e.g., from 50°C to 60°C) and test.
• Open radiator valves: Make sure manual lockshield valves and any non-Tado TRVs in the room are fully open.
• Check other rooms: If some rooms are very hot and others cold, your system may need balancing. Slightly close the lockshield valves on the hottest radiators to push more flow to colder rooms.
• Verify Tado head position: Ensure Smart Radiator Thermostats are correctly calibrated and not stuck in a nearly closed position (re-run calibration if needed).