Smart radiator thermostats (TRVs) do not open or close properly; some rooms stay cold or hot

Safety first: Radiators can be hot. Use gloves and avoid contact with very hot surfaces.

• Check batteries: Replace TRV batteries and ensure the cover is secure.
• Verify adapter: Confirm the correct valve adapter is used for your radiator valve body and that it is tight.
• Free the valve pin: Remove the TRV head and gently press the radiator valve pin in and out with a blunt tool until it moves freely.
• Recalibrate TRV: Refit the TRV and run any available calibration routine via the Wiser app or TRV button sequence.
• If still unreliable: Replace the affected Wiser Smart Radiator Thermostat.