Underfloor Heating Question...

[HDog]

Hi

I've recently had wet underfloor heating fitted to my new extension, a largish L-shaped open plan room which circa 7m long by 5m.

How can i tell if it is working correctly? It seems to take a long time to heat up, e.g the return pipes on the manifold remain cold for circa 2 hours when then heating is constantly on. As a result you get a warm floor in half the room and it will still be cold on the other half?.

Anyone have an idea how long it should take to get warm water circulating around the whole system and hence have an even heat throughout the whole room?

[HDog]

Thanks for the responses chaps, i've attached some pics which may help to clarify.





I do have the flow meters on top of the manifold, if i play with the black collar will this adjust the flow rate? It never seems to change currently, always sits at the top of the meter reading circa 0. What should this be showing?

[HDog]

Thanks for the help SS

Bit of a lamens question this, but how can I tell if the pump is actually working correctly without taking it all apart?

Also, the white caps on the return pipework (actuators?) seem to be just plastic caps which you can tighten or loosen. Currently they are fully open so I would imagine this would facilitate a maximum flow rate? I'm still getting no movement on the flow gauges from the 0 reading they currently show.

[HDog]

Okay so last night I had a play with the flow valves, turns out they are fully open (as i managed to completely unscrew one of them and it popped out!)

It looks like the main valve is opening when heat is called for so there is hot water coming from the boiler to the top manifold and into the pump. I unscrewed the bleed screw on the pump and water flowed out so i guess there is no air lock in there.

Any other suggestions? the flow readings are still not changing from 0 when have the UFH switched on or off.

[HDog]

Fuzzy400 said:

From what i can see from the photos, your manifold is made arse about face. The pump is pushing water the wrong way round your system. Water will go through the flow indicators (top barrel) the wrong way but not very well and they will always read zero.
The way to correct this is to turn the pump the right way up and the swap the flow pipework (with the thermostatic head on) with the sensor so you'll end up with the flow connected to the bottom left of the manifold and the sensor connected to the top left. The sensor is on the end of the wire running from the thermostatic head.
Check everything is open, flow indicators on the top barrel, manual heads on the bottom barrel and the return (white cap bottom right) is open. If the pump works and the flow and return pipework from the boiler are the right way round then your system should work.

Thanks for this Fuzzy, sounds like I could have some serious installation issues then? This does sound plausible as I've turned the pump to max and could hear a change in tone so I guess that is working fine.

Sounds like I will need to get the installer back, but as he put it in I guess he thinks it's correct!!