Comments on heating system design?

[Crowbar hero]

We are having UFH in the new extension, with a desire to retrofit UFH into the existing house when we start renovating that in the years to come.
As we are relocating the boiler into the extension as part of this plan, the entire plumbing and heating system is up for review.  The UFH system is from Wunda.
The layout is a little tricky due to the fact we cannot get a single manifold in a central location downstairs, so there'll be multiple manifolds at work.

I've attached a schematic of my initial thoughts for hooking all this up, I would be interested to know if there are way I can simplify and/or optimise this system at all.

Other comments most welcome too..

511 heating schematic.pdf

[JohnMo]

Sorry lots of comments as I think your being taken for an expensive ride.

 

I would say the scheme way to complicated for its own good and your sanity.  The boiler only ramps down to 7.1kW if you have only a couple zones operating your boiler will be shutting down and starting up like no tomorrow, using lots of gas and provide little or no heat.

 

You need to make sure all the pumps are hydraulically separated, a series of close coupled tees will do. You may need to look at the return flows also.

 

First thing is dump all/most the room stats, they will just cause the boiler to short cycle and use loads of excess gas. Also operating as one or at most two zones will let you remove the motorised isolation valve from upstream of each manifold.  The pump will pull the water through as needed.

 

I would dump all the smart stuff and use a single glowworm controller in a central location and outside temperature sensor and enable weather compensation.  Then balance the room flows to get the temperature you require.

 

You don't need UFH in the halls or landings, they will get heat from the pipes going to rooms and borrow ambient heat from everywhere.  We have UFH in the bedrooms and I would say to anyone don't do it.  Way to slow respond, radiators or fan coil, then at least you can implement cooling later when you have a heat pump.