I would disagree about the "ball park figure" being adequate to start with,
the odds are you will end up with a boiler and radiators which are too
small. Bigger IMO works best for heating systems, this applies to boiler
and radiators. Of more importance, where are the 10 year maintenance and
running costs factored in on a combi system without soft water. How do these
costs compare with a traditional conventional vented boiler, even allowing
for a tank replacement every 10 years?
Thinking about it, are there any boilers of any type with a 10 year warranty
even with soft water? In the past, my boiler life achievements were in
excess of 20 years, have these days gone forever?

Regards
Capitol



IMM wrote in message ...
"Andy Hall" wrote in message
.. .
Any recommendations for sources of information on
designing a central heating/ho****er system for please.

have found sites that provide info on rating the boiler/rads
but nothing on the actual design. type of heat storage etc.

duncan
snip

Buy a high flowrate combi. Not all combi's
give a trickle for hot water. They
are easy to install with minium design in
CH pipework and rad sizing.

You connect up 5 pipes, run a power supply
and a wire for a thermostat or thermostat/clock
from the combi. Superb for high pressure showers.
A doddle.

The radiator sizes and pipework still need
to be calculated properly Use of a combi
doesn't make a fundamental difference to this part of
the design.

Don't go for complicated cylinders, tanks, motorised valves, control
systems, etc when there is no need to.

Come on. It's not that difficult.

A one box solution that professional experts have incorporated all the
design and components is by far the best option.

We don't know whether Duncan has a
requirement that doesn't match a
combi.

That's why I said get back to me.

The rad sizing can be done by using
one of the many on-line rad calulators.

These are useful, but are not bug free.
I have seen mistakes in the
U value numbers in one program and
another doesn't calculate heat
gains properly.

They give a good ballpark figure.



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