Search the forum,

Discuss Strange UFH behaviour at manifold in the Water Underfloor Heating Advice area at PlumbersForums.net

Messages
3
Hi,

Hoping someone can comment on whether what I see happening at my UFH manifold is OK, or whether there is cause for concern. I'm not an expert on underfloor heating, Our system was fitted about 10 years ago and has worked flawlessly with zero issues all this time.

As you can hopefully see from the photos, I've got two pipe loops, both going to the one zone (kitchen).
The first weird thing is that I've noticed that the flow meter on the left hand loop is always stuck on about 4, even when the pump is not running and the thermostat is off.
The other flow meter works fine.
The first photo was taken when the system is running. Both pipes are hot going into the system and coming back out and I think I can feel water vibrating through both return pipes.
When I turn the thermostat off, the right hand flow meter returns to zero and the left stays on the current 4 rate.
If I adjust the actuators on the returns, I can make the right hand flow meter adjust up and down as expected. The left never changes.

OK, I thought, that's probably a stuck flow meter on the left. That'll need fixing some time.

But then I noticed something else. As you can see in the photo, the lower return cold valve tap appears to be closed. That seems wrong to me. Doesn't that mean the water is not flowing back through the system? The upper red valve is open (in line with the pipe)

So... I opened the blue valve (to the same position as the red, in line with the pipe) and... the right hand flow meter rises straight back to zero. Indicating no flow of water. (Obviously the left remains unchanged at all times - as above, I think it's a stuck flow meter so ignore that for now).

Blue valve closed = right hand flow meter on 4, Blue valve open = right hand flow meter returns to zero.

I guess the main question is ... am I correct that both the red and the blue valves should really both be in the open position?

If so, why does my one working flow meter drop to zero when I open that valve, and why does it return to '4' when I close the valve?

Here's the system running, all pipes hot, blue valve closed:-

UFHPic.jpg

And here, with the blue value open, see the flow meter top right shows no flow.
UFHPic2.jpg


Final point - I'm no expert on this. I'm happy to be told I'm just a fool misunderstanding how this all works :)

Thanks for any advice anyone can pass on.

Ian
 
Probably the blue handle has been put on / removed and re fitted the wrong way
 

Reply to Strange UFH behaviour at manifold in the Water Underfloor Heating Advice area at PlumbersForums.net

Creating content since 2001. Untold Media.

OFFICIAL SPONSORS

OFFICIAL SPONSORS

Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock