Underfloor Heating broken

[cold-feet]

Hello

Underfloor heating installed in 2019 - no probs at all. Suddenly stopped working yesterday.

Thermostat is starting the pump, and lights come on. Pipe is very hot at point 1 - and cold at point 2

I have also noticed a leak at point 3

My theory is the motorised valve has broken - and the pump may have caused too much pressure at point 3 - causing a drip. It is leaking onto a chipboard wood board - this is damp but not soaked - suggesting it's all a bit recent.

I have turned off the UFH at the stat - but i can see the red butterly tap (3) still weeping - seemingly from the spindle itself

GCH and Hot water work fine. I can see motorised valved for GCH move slightly when activated - so i was expecting to see same for UFH valve - which leads me to suspect the valve for the floor.

I can manually open the "underfloor" motorised valve, and everything gets hot again (3 still drips a little) - based on this i am very suspicious of the motorised valve being broken. I believe that it is possible to just replace the motorised portion of the valve and stay dry. With the electricity isolated i may even avoid killing myself.

Also - the valve (3 on photo) is weeping at the spindle itself - and this is on the return side of the manifold

Does replacing this mean draining the system - i just don't know enough to be confident to give it a go ?

I have calls out to a couple of plumbers but no joy as yet in getting a response - i am just trying to understand the issue at this stage. I would contemplate changing the motorised valve, but the tap shown in (3) fills me with fear - and i don't want it also filling my house with water

Any thoughts welcome

I have purchased slippers in the meantime

Cheers in advance

Si

Any thoughts theories / engineers very welcome

 

[Deleted member 120897]

You can probably get underfloor heating, with the gch. It’s likely that the zone valve has failed, which you’d be correct. The valve head (actuator) needs to be removed, for it to work with gch though.

The butterfly valve, would likely need a partial drain down to replace, or someone with a freeze kit.

 

[ShaunCorbs]

Butterfly valve is probably just a gland remove the red handle you might find a nut that you can pinch up