Ufh

Evening all,

I am got a small problem with a two zone ufh. One of the zones has stopped working. I am just trying to locate the problem and just after some advice.

I have been to check the wiring and the thermostats. When they are asked to heat the lights on the wiring centre lights up, the boiler kicks in and the actuators open up. Still no heat. Would air in the system prevent a zone from heating up even though it has been working fine for a year? Any other suggestions would be appreciated. thanks

Are the pumps running? With wet under floor heating to limit the floor temperature the feed and return water is blended to adjust water temperature, so there is a pump that circulates central heating water around whole system and one which does a local circulation.

They are not all the same, so you need the manual on your manifold can't really help in general terms. There may be some one who can help, but they will need info on what your system is.

Ideally each loop should have a small flow indicator - but I suspect few do.
I would suggest removing the actuator head for the zone concerned - which I think should let the valve spring open. The zone should then heat up when there is demand on any of tbe zones.
One common problem is valves sticking shut that haven't been exercised all summer. When winter comes, a radiator (or in this case, UFH zone) then doesn't work. Once you've ruled out hydraulic problems, you can return to electrical ones ...
Obviously do the normal tracing - is power applied to the actuator when the controls call for heat ? If so, and you've ruled out hydraulic issues, then the head is suspect - they do fail. When testing, just remember that they can takes minutes before power on/off and actually moving due to the way most of them work.