Hi iv installed underfloor heating before with a manifold, but not with two manifolds, one upstairs , one downstairs, has anyone done this and what additional cables need to be run ?

Partly it depends on the plumbing system and whether it's to have a 2-port valve for each manifold (or whether the two together are treated like one long manifold) and of course whether a 12V 'network' system or 230V. If it's based on HeatMiser kit (which of brands seem to be) try their web site: http://www.heatmiser.co.uk/web/index.php/docs

- Andy.

It's made by jg speedfit , I thought they only had valves when rads were being used, so it needed a rad valve ? Or if the hot water was run off the manifold too so needed a hot water valve ?

I'm pretty sure Speedfit are re-badged HeatMiser.

Sometimes, where the boiler is supplying UFH and other things (rads, or HW cyl) there's a 2-port valve between the boiler and the UFH mixer & pump, to stop circulation around bit of the UFH circuit when it's not wanted. The UFH system then just looks like one leg of an S-plan system to the rest of the plumbing. It's not the only way of doing it of course though.

Yes, there'd normally be conventional 2-port valves for any rads and DHW (unless there's a high temperature manifold to do the equivalent).

If it's the network version, this might help: http://www.heatmiser.co.uk/web...network-install-guide

- Andy.

Andy,

You are correct, I done a "speedfit" system last year for a sparks that couldn't and that was heatmiser rebadged.

Heatmiser now do a very nice wireless solution for the stats, it's even clever enough to cope with radiator or UFH zones


Stu

I'm just getting quite confused with the wiring etc, I have done underfloor heating before, and the boiler controlled the hot water. But now it's two manifolds and also hot water tank. Anyone shed any light please ?

It depends how the plumber has plumbed it.

How many motorised valves are there. I'd guess at three ??


Stu

It's not at that stage yet it hasn't been plumbed in. Not sure how to factor it all in

Find out what sort of control gear is being used. For example heatmiser/speedfit do systems that either require mains cabling to the room thermostats or cat5.

Then once you know the answer to that, I'd run a 6243y + t&e between the manifold controllers and the airing cupboard. The same between the boiler and airing cupboard. If you can't get an answer at this stage, stick a cat5 between them as well for good measure.

Assuming you can put a single channel programmer/time clock in the cupboard along with a bit of a wiring centre you should have enough wires in the right places. Obviously stat cables back to manifold controllers.

The rest is simple, the valves and pumps for the ufh connect to the controllers with a pair to "call for heat", the water you do with a tank stat fed from the programmer to drive the "water" valve on demand and the contacts on the water valve do the "call for heat". The system pump will probably be controlled by if not in the boiler to allow it to overrun.

Stu