Correct adapter to use for my radiator?

vab

Hi,

I would like to fit a tado smart radiator thermostat on an ultraheat radiator in my house. I am unable to fit it on with the default adapter. Which adapter should I use for the radiator in the images below:

Regards,

GrilledCheese2

Possibly the M28 x 1.5mm adapter.

https://intercom.help/tado-hc/en/articles/3405520-how-do-i-mount-the-adapter-for-m28-x-1-5-valves-to-fit-my-smart-radiator-thermostat

vab

I used that adapter and it fits on fine.

But when the heating for the house is on and the radiator specific temperature is set to off the radiator still gets a bit warm.

Any idea on what to do in this situation?

GrilledCheese2

It sounds like the valve is not closing properly, allowing hot water to pass through. If the metal valve body is old then the valve may no longer operate properly. Check the original TRV head closed the valve fully. Alternatively the pin is not long enough. Did you use one of the plastic pin extenders that came with the adapter? If you did, then try a longer pin extender. Removing and re-attaching the TRV head will cause it to recalibrate.

vab

Changing it to a 18.5mm pin (comap valve) worked.

Thanks @GrilledCheese2