On Sun, 28 Aug 2005 12:26:22 +0100, Dave Fawthrop wrote:


I am thinking of replacing my conventional central heating and hot
water system with a gas combination boiler, for my four bedroom
extended semi, with one bathroom. My present system is 25 years old,
when I did the heating calculations and ended up with a 10kw boiler,
which works perfectly well with ample heat output, even in the coldest
weather. When I did the heating calcs, the house was *very* well
insulated, and I have continued adding insulation/double glazing over
the years, so it is now *extremely* well insulated. I am therefore
looking for a combi with less than 10kw output to central heating,
plus enough say 10l/m to the DHW.

Objective is to save space.

I have looked in Google Groups for old threads, and tried to answer
the questions which may be asked.

Kitchen tap gives 16l/m
Bath tap hot water gives 9l/min
Soft water.

Googleing for combination boilers only gives huge 20+kw models does
anyone here know of anything smaller?

As I will now be pressurizing the central heating pipes (copper with
Yorkshire fittings) does anyone expect problems with this?


The lowest gas rate I've seen is an 18kW Vaillant unit made around 15
years ago. This will provide an even more limited flow of HW than the
'standard' 24kW units.

It might work for a small dwelling with no bath.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
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