Any Gas Central Heating Geeks Around?

[Thomk]

I’m having a new central heating system put in inc. system boiler, unvented cylinder, new pipework and rads. I want to use this one system to heat both the main house and our “granny” annex (to be built later this year). The annex will have underfloor heating preferably organised into 4 zones.
My questions are:

1. What is the best way to be able to control the heating requirements in the 2 areas (house and annex) independently and….
2. Also be able to control the 4 zones in the annex independently and….
3. Also be able to control 2 zones (upstairs and downstairs) in the main house independently
4. Work our reasonably accurate bills for the annex gas usage

Any help with this much appreciated

 

[Archie_tect]

Underfloor heating circulating at 34 degrees doesn't need direct heating from the boiler as it'll be too hot... so feed from a separate flow and return coil. Get a good plumber in early who can give you the advice you need to design and balance the system Thomk, not worth trial and error... complicated valve zone controls are sophisticated these days... or you could go for a modular boiler... include an extra coil in the cylinder for future solar hot water panel connections.... and go for as big a HW cylinder as you can fit as a heat store.

 

[Thomk]

Underfloor heating circulating at 34 degrees doesn't need direct heating from the boiler as it'll be too hot... so feed from a separate flow and return coil.

OK this sounds like Klingon. What is heating the underfloor pipes if it's not the boiler?
I do have a heating engineer on the case but zoning is a tricky business and I wanted to get my head around it.... and he says that there is no easy way to "sub meter" the gas usage.
I'm planning to install a 250L tank.
I think I'm going down the pv route rather than solar thermal but could still be persuaded otherwise.

 

[Archie_tect]

The feed and return circuit from the separate coil in the HW heat store.... There's a fantastic Heating and Ventilation Exhibition Centre in Lemington Spa run by Wolseley... I'll have a look for the website- worth a visit even if just for an informed chat and ideas.

...and if you can visit the Ecobuild Exhibition on in London at the start of March [http://www.ecobuild.co.uk/]

 

[Thomk]

The feed and return circuit from the separate coil in the HW heat store.... There's a fantastic Heating and Ventilation Exhibition Centre in Lemington Spa run by Wolseley... I'll have a look for the website- worth a visit even if just for an informed chat and ideas.

...and if you can visit the Ecobuild Exhibition on in London at the start of March [http://www.ecobuild.co.uk/]

Great Leamington is not far from where I live.

 

[Thomk]

I was hoping that I could have a motorised valve to separate the 2 main zones (house and annex) and then the sub zones in the annex would be controlled by the actuator on the manifold. Not sure how to zone the 2 remaining sub zones in the main house though.

 

[Archie_tect]

The Wolseley Centre.... http://www.wolseley.co.uk/corporate-responsibility.aspx + great site for everything you could possibly want!