"David Hansen" wrote in message
...
On Wed, 8 Nov 2006 18:51:40 -0000 someone who may be "Doctor Drivel"
wrote this:-

You are missing the point. You can
make a stored water system deliver the
required full flow with all taps full on.
It will be very big

Incorrect. It is likely to be larger than
one typical size cylinder, but how large
it is depends on the house.

That is in effect what I said, so I was correct.

Running the same lot with
instant water heaters (aka combination boilers)
would involve at least say five such heaters.
A very expensive capital cost for no
gain.

The house is two bathroom 3 showers. To get full flow and volume from a
stored water system from "all" taps fully on, and that includes sinks,
basin, etc, it will need to be very big indeed and far more extra expense.
Very large cylinder, or cylinders, large bore pipework all over the place,
etc. In effect a commercial setup. A small hotel would need a system that
can fully cope will all outlets on as guests bath and shower in the morning.
Their usage is very spiky. Domestic systems are designed to cope with
"average" use, so upping it to commercial specs is very expensive for no
gain.

The same applies to instant hot water (not just combis as you said). Banks
of staged multi-points can be used that switch in on water demand. A
commercial setup. Not much to be gained in a domestic house of two baths
and 3 showers for all the extra expense.

What you wrote was:
"Despite what some may claim, instant
water heaters, of the sort one sees in
houses, won't run all of this lot".

Some actually will. However you are
not familar with these sort of
installations.

Your assertions about what I am or
am not familiar with are mildly
amusing, but they are still incorrect.

You are clearly not familiar with instant hot water, otherwise you would not
have written what you did.