"Christian McArdle" wrote in message
news:3ffada55$0$9388
Well, it sounds like you might have a mains cold supply. If so, a venturi
based shower might be ideal for you. The flow rate is not quite as good as
a
power shower (which probably appeals to you!), but it will be much better
than the feeble electric shower. It also means the water is heated by gas
at
a fraction of the running costs of electric. So you save running costs,
installation costs AND get a much better flow.


The current bath has hot water from the boiler and cold water from the attic
storage tank. However there is mains water into the bathroom for the cold
tap in the sink, so it probably wouldn't be a huge job to pull that across.
I've had a look at venturi design at this URL:

http://www.brookwater.co.uk/jetstrea...i_mainpage.htm

I understand how it works in principle, but remain slightly sceptical ...

If you don't have a mains cold supply to the bathroom, then a twin
impellor
pump might be worth having. This will also benefit bath filling. The final
other alternative is an all-in-one power shower which consists of a single
impellor pump after an internal mixer. If you choose a shower with a flow
control, you don't have to have the full deluge, but you'll still save
loadsa money on water heating and it will be easier to install, as the
electricity can come off a nearby ring main (via a 30mA RCD FCU if
necessary). It doesn't require a 10mm cable run specially for it like an
electric shower.

What's the difference between twin and single impellor pumps? Or more to
the point, what's the reason for either? The only reason to not go for a
power shower for me is that it will run out the hot water too quickly. The
electric shower my parents has is just a cord pull to heat the water it
produces, which surprisingly comes out at a reasonable rate.

Try setting the timer to heat the tank for you! In fact, running it close
to
24h a day (or off from 23:00-5:00) isn't a bad idea on a modern insulated
tank. The temperature drop during the course of a day isn't sufficient to
make not doing so much more efficient.

There's a lot of loss through the pipes in our house (1935 vintage) - some
touch floorboards and heat the floor! Nice in the winter, pain in the arse
during the summer! Leaving it running all day I think would be wasteful as
I'm only awake/there for about 7 hours a day!



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