On Sun, 30 Jan 2011 20:33:46 -0000, "ARWadsworth"
wrote:

There is no "wasted hot water". There are of course the losses in the pipe
work from the combi to the taps

Or more precisely there is lots more lukewarm, cold, and scalding hot
water wasted in a combi installation and significantly more firings of
the boiler.

A typical scenario:

Every time you turn the tap on you get bugger all hot water, by the
time a combi has fired and water is flowing in the pipe to the tap
then nine times out of ten you'll have thought f*ck it, I can't be
bothered to wait this long for hot water. So you turn the tap off.
Then some time later someone else turns the tap on, they get a spurt
of lukewarm water, then cold, as the boiler fires up again on yet
another wasted exercise. This goes on all through the day and all the
boiler is achieving is a warming up of pipework. Then two people turn
on a tap and get cold water then possibly lukewarm water, then one
turns the tap off and a gush of almost scalding hot water comes out of
the other tap.

The only time you'll get continuous hot water is running a bath or
taking a shower. The shower will work, but if someone else turns a
tap on it could scald you or leave you covered in ice cold water. The
bath might even fill before the boiler needs an annual service
although you probably have to start filling it the moment the service
person walks out the door.

I'd sooner bathe in a tin bath in the middle of a snow covered field
than ever have a combi.

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