Brendan1919

In the pic the pipes are directly under the airing cupboard and switches for CH and HW. The boiler is in the garage behind the wall where the manifold is positioned. When it’s in not working state the hot water pipe (left hand side) is luke warm. When I switch central heating in it gets red hot. At first it is hot from ceiling to the pass off to the UFH. And they remain cooler beyond the pass off to the floor. After an hour they are hot. I’ve also observed when it’s in not working state the pipes in and around the switches in the airing cupboard are always hot. It’s as if the hot water gets to the switches and stop, trickle trickle through. Then fully pass through when central heating is on.

Hi, thanks for the replies. The UFH probably has never worked properly as only just noticed now having to keep an eye on bills. Observed when only trying to heat floor and leave rads off in winter. Q1 response - The pump is in the boiler. Q2 response - The radiator on the landing, next to the airing cupboard with unvented cylindar and switches does get warm when UFH is on and CH is off.

Yes they all have their own thermostats, the idea was to have different heat in different zones of the floor area. So are you suggesting we set all three thermostats to the same temp and see if all three loops calling for heat will enable the boiler to fire and stay fired up to ensure the flow makes its way to the manifold?

The room thermostats are connected to the wiring centre for the ufh, so the actuators open up and call for heat when needed. However unless the rads are on then the hot water flow isn’t sufficient. We have ufh set to be a constant temp as primarily live in this space. The rads in rest of house just come on for an hour in the morning and for 2 hours in evening when we bath, go to bed etc. Would’ve thought we could run each heating system independent of one another?

Thanks both for speedy responses, really appreciated. The boiler is firing up and like you say times out and tries again. Before exploring the buffer option, how would I check if the UFH boiler signal is into the boiler direct instead of the wiring centre?

Hi, hoping one of the UFH experts can help with an unusual issue 🙂 When the central heating is off and the UFH is calling for heat - the actuators open up, the boiler fires up, however the hot water feed to the ufh mixer valve is lukewarm and temperature never gets above 24 degrees going into the loops and return is 20 degrees. Therefore the floor never reaches desired heat on the thermostats. However, when I fire up the central heating, the hot water feed to ufh mixer valve is red hot and and temparature reaches 45 degrees going into loops and return is 45 degrees. The floor then warms up over the next 2 hours to desired heat on the thermostats. Why could this be happening? The ufh supposedly has its own feed from the boiler, so should be independent of the central heating. Ive attached pics of the ufh pipe work, manifold and actuators. Also a pic of the 3 way valves for the central heating and hot water for the unvented cylinder - both set to auto and running via hive system.