Uponor underfloor heating valve.

[Christopher buzzard]

Can some please identify the valve on this underfloor manifold ( with the black wire coming out of the top). Have an issue where the system is turning off every 10-20 minutes and staying off for a while then coming back on again. The room can’t get up to temperature because of this. Power was going to the valve but not out of it.
‘thanks for your help.

 

[oz-plumber]

It looks like an temperature sensor on the heating outlet of the pump.
If the temperature gets too hot the pump will stop operating - to protect the UFH pipe and the floor.

Adjust the mixing valve to get cooler water or it could be a faulty thermostat sensor

 

[Christopher buzzard]

Hey. That’s for your reply. Must be the sensor faulty then as the thermostatic control on the flow in, was working ok And controlling the temperature. I linked it out last night just to prove there was no other issue. Going back in today to see if the room is up to temperature.

 

[Brambles]

Christopher,

That is a TM manifold, the originally fitted high limit stat will be hard to source. The current Uponor part number is 1002371 - which may need a threaded insert to fit.

Don’t be tempted to just bypass the limit switch

 

[Christopher buzzard]

So only there if the thermostat head on the flow, fails and or if the boiler thermostat fails?
Never seen them on a manifold before. Spoke with an electrician who said in the past he hasn’t wired them in. (Not saying he’s right to do that though)

 

[SJB060685]

So only there if the thermostat head on the flow, fails and or if the boiler thermostat fails?
Never seen them on a manifold before. Spoke with an electrician who said in the past he hasn’t wired them in. (Not saying he’s right to do that though)

Yes in the event of flow temperature being too high due to whatever reason this will isolate supply to protect floors and pipework as said above.

 

[Christopher buzzard]

Thanks for your reply. Much appreciated.

 

[SJB060685]

Brambles is the man on these so he is worth listening to lol. As he said linking out is not advisable, in many cases will give a quick fix or in this case find a fault but it shouldn't be left like that.

 

[Christopher buzzard]

Hey. No will def sort a replacement sensor. Just need to make sure there’s no other issues. With the manifold in the cellar and pipe loops above my 1st thought was air in the loops. Will report back later.