Question about Underfloor Heating connections.

[Mark]

Hi a couple of months back, I installed UFH in my conservatory, I fitted the manifold and pressurised it, and then screeded, I have now come to properly connect it up to my main radiator feeds, and realised I may have a problem...

I have a room thermostat in the hall, which wirelessly connects to my combi (Worcester Bosch 35CDii), I now also have a room thermostat in the conservatory, which opens the UFH circuits, and kicks the pump in for that.

It's occured to me, that there could be a situation, where the thermostat is requesting heat, and switching on the pump, but the boiler is not on, because the hall thermost says the house temp is fine.

Hope I am making sense here...

Now I am wondering, does combis generally have flow sense, like on the taps, when water flows, it kicks the boiler into heating? As that may fix my problem, so the UFH pump will start circulating, and kick the boiler into life...

I suppose my other option, is to get another wireless transmitter and pair that up with the boiler, and fire that when the UFH thermost box lights up.

Can someone enlighten me? Thanks.

[geoff]

In message , Mark writes

only on the hot water side

[Heliotrope Smith]

Your boiler will not fire up unless the stat in the hall is calling for heat. With your 'other option' the boiler will fire when UFH calls but the boiler pump will also kick in. You will not be able to have UFH on without the rad circuit being on at the same time but it seems like you can have rads on without UFH.

[The Natural Philosopher]

Aboslutely.

I dont think so.

No, what you do is hget a relay, put its coils across the UFH pump and its contact across your existing radio stat.

You DO have motorised valves to separate the UFH and the radiator zones don't you? and a two way timer..timings for UFH need to be several HOURS ahead of radiators, if its in screed..