Noisy thermostat

Foleyart

Howdy. I have underfloor heating in my house, wood pellet which I am quite happy with. However there are two rooms upstairs, sitting room and office, I know strange design. There is a thermostat on the manifold which makes a terrible vibrating noise when the heating is on, and I mean just the system, not the actual underfloor upstairs. I had thought originally that it was to do with lack of pressure in the system but that is not the case. It is one of those thermostats with a probe on the end of a copper wire and I am not exactly sure of its purpose. The noise it makes can be heard all over the house as it is a low frequency vibration. Any ideas??

knx

Are you quiet sure that it's a thermostat. Can you post a picture.

JamesM

I remember water flow used to cause that type of vibration with some thermostatic rad valves when they were set half on. try turning the thermostat a bit up or down - see if it makes a difference.
Jim.

Foleyart

Hope this works ! It goes off briefly when you turn it up or down

knx

That certainly is a thermostat alright. Just like a rad valve. I wonder is it screwed on tightly. Try tightening it with the silver ring under the stat body.

Foleyart

Tried that already, no joy. thanks for the input though.

youtheman

Try the opposite to what knx suggested. Unscrew the TRV head and remove it altogether. Then press the 'tit' on top of the valve (it has a spring). See if its free. Press it in and then allow it to come out (in stages) to see if you get a repeat of the vibration. This might help ascertain if its the valve of the TRV head.

youtheman

Another thought struck me. The head on a TRV normally senses air temp. But the pciture you posted seesm to suggest it has a 'capillary' tube which is sensisng the temp somewhere else (maybe water temp?). If I was a betting man I'd say that the tube is either broken, disconnected or damaged. Still worth doing the test I previously suggested.