Wth underfloor heating manifold

[joe plumber]

Got called to a bit of a house of horrors today. On the list of things that didn't work properly. Was a wth underfloor heating manifoldhttp://www.homebuilding.co.uk/sites...gallery/thermo_floor_southern_manifolds_2.jpg this is what it looked like it does the whole of the ground floor 5 zones in total. The problem being that it doesn't seem to work at all. It's fed off 28mm pipework and the flow in is hot. However the dials on tthe manifold never rise above 40degrees even with the mixing valve set to 55. I'm no expert on ufh but I understand the principle. My gut feeling is the pipework under the floor has not been laid in the correct way eg Celotex then screed. Oaybe the loops are too big. As heat seems to go in and never return. Just thought id ask on here and see if any of you guys had any experiance with these manifolds.

Thanks

Joe

 

[stevetheplumber]

ufh heating is usually run around 40 degrees it takes days to warm up from cold especially with it being this cold