Albion and Range are big boys making mainly standard products, but will
custom build to suit (at a price). DPS are smallish but leading edge in
technology having a few patents about. All use standard of-the-shelf
components.

http://www.abion-online.co.uk
http://www.range-cylinder.co.uk (go to thermal storage)

What you "need" is an "integrated" heat bank with: vented, with integrated
feed and expansion tank, and all electrics wired in, with electric backup
(DP and Range do these), Albion only do thermal stores. Heat banks are
now virtually the norm.

http://www,glendhill.net, Do heat banks and make excellent stuff. Not
cheap, but will deal with a self builder, but they mainly deal with large
customers such as large house developers. Some of their components are
dedicated to their products.

Sizing up an integrated heat banks is different to sizing a DHW only
model. One being larger.

Note: a vented heat bank can be on the same level as your highest rads.

Thanks for all that, I'll do some more surfing. Any reason why the heat bank
can't be on the ground floor with a header tank above the level of the
rads?


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