Thermal Store - Overall Control and Weather Compensation System?

[martin W]

Also would two pumps on the central heating (one per xzone) be ultimatly more effective and reliable instead of 4 way mixing valve, plus the two zone valves? I suppose it will depend a lot on heat demand of the zones. My cheap Wilo Smart pump uses around 35 watt on speed one, I think the latest Grunfos are around 15 watt or less so runing cost owuld be paid for in savings on valves etc.

[wookey]

I've spent a long time thinking about this stuff too, and made a long list of tank suppliers about 3 years ago. I failed to find a tank I liked at a price I was prepared to pay, but several new suppliers have appeared since. http://www.navitron.org.uk/pmwiki/pmwiki.php?n=SolarThermal.Tanks
If you wanted to update the wiki with the new prices/suppliers you've found that would be useful.

You might want to check out the idea in the Rebus project as one nice way of designing a system: http://www.navitron.org.uk/forum/index.php?topic=2630.0

[dan_c]

I've just realized there have been several replies since my last post - thanks for your comments. I have only skimmed over and will read through them all in more detail shortly.

For now I will answer the question/point about insulation:

I have draft proofed the whole house as best I can now - this was done before redecorating so it was fairly comprehensive. I have approx 450mm of insulation in the whole attic (excluding 100mm Celotex in my small boarded out area). I have replaced approx 20x 1990s double glazed windows with new in the last eight months, and fitted a new well insulated composite front door. My wall construction is brick, 65mm cavity, 125mm lightweight insulation block, dry lined and skimmed. There is no insulation in the wall cavities though and I can't add any as the brickwork has 10-15mm recessed pointing and so nobody will fill the cavities. Total external wall area is in the region of 280 square metres - that's big money to rake out and re-point.