On Sun, 14 May 2006 14:23:09 GMT someone who may be John Stumbles
wrote this:-

But before going further may I ask:
1: is your house already draught-proofed and insulated to the highest
standards

Cavity wall and loft insulation, to the greatest extent possible are
certainly important, as well as cost-effective draught-proofing.
Important for reducing heating costs.

However, none of these affect hot water production to any extent.
What matters is the layout of the house and the services within it.
Insulation of the hot water pipes is certainly a good move in many
circumstances.

2: does your heating system already have thermostatic radiator
valves, a programmable thermostats and - if the house is not absolutely
tiny - separate heating zones

Important for reducing heating costs.

3: is your combi already a high-efficiency condensing type?

If it is not I would ask questions about how old it is. Replacing a
relatively new boiler is not sound financially or environmentally.

If the answer to any of these questions is No then improving the relevant
area(s) is likely to make more sense both economically and ecologically
than spending £1000s on a solar water heating system.

Economically solar water heating is still a long term investment, at
current fuel prices. However, the price of sunshine is not going to
increase, unlike other fuels. There are also other advantages, such
as being able to largely turn the boiler off in summer and thus
(probably) prolonging its life. If it is the sort of combination
boiler that has a small hot water cylinder this will also save some
gas.

Environmentally solar water heating is an excellent investment.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54