UFH, 2 manifolds on one mixing circuit?

Vertical

I’m installing underfloor heating upstairs and downstairs. The boiler is upstairs near the upstairs manifold, the downstairs manifold is downstairs (approx 5 metre pipe run from the upstairs manifold).

Rather than installing two separate mixing circuits I’m thinking of installing 1, as this will save me a pump, mixing valve etc. as well as simplifying things (see picture).

I realise I might need to balance the flows to the upstairs and downstairs manifolds, but can anybody tell me if there might be any difficulties given these pipe sizes (with flow rates, etc)? Specifics are on the attachment.

Any input appreciated.

davidoco

One thing to make sure of is to fit an alpha pump http://www.gasapplianceguide.co.uk/alpha_pump.htm which will adjust itself to the flow required.

I've not done it but most specs you see for underfloor show seperate pumps for each circuit and I presume it's because standard flow pumps can't handle the variations in flow required for underfloor and burn out quickly.

I don't know what controls you are looking at but www.heatmiser.co.uk have nice programmable stats which together with their wiring box makes underfloor very easy for the diyer. The whole package is not cheap.

Ewan

Lads, is there any good sites or literature where i can find out all about underfloor heating....everything from loops, pumps etc.. to insulation....