Room thermostat keeps breaking....

[sii4]

Hi new to all this......

I have a 5 year old condensing glow worm bolier and a Danfoss control system to include room thermostat.
The problem I have is that the central heating keeps stopping working on the thermosat. This happened a few times last winter and as soon as I replace the thermostat with a new one it works again!
All ok on hot water and when hot water on it also heats some of the rads.

Any ideas as to why the thermostat should keep breaking??

 

[45yearsagasman]

Maybe its not the room stat but a siezed/sticking 3 port valve.Rads heating when on hw only points to valve.Stop replacing parts until correct diagnosis of fault.