On Fri, 27 Nov 2009 15:42:39 +0000, David J wrote:

I have been wondering how to measure the 'effectiveness' of adding CWI
to a domestic house, apart from seeing the resultant change in energy
costs at a much later date.

You could get a reasonable estimate using the whole house boiler sizing
method to estimate the total heatloss of your house and do the calculation
with and without CWI.

There are links at
http://wiki.diyfaq.org.uk/index.php?...Heating_Design to some
online calculators, and a spreadsheet with which you can easily do what-if
calculations.

--
John Stumbles -- http://yaph.co.uk

Little Johnny's gone away, his like we'll see no more
For what he thought was H20 was H2SO4