"Christian McArdle" wrote in message
.. .
A pump located under the bath would be a possibility. *But* you will also
need to plumb in a low pressure cold feed from the cold header tank
rather
than using mains.

Actually, provided you use a pressure balanced mixer, it is entirely
possible to mix mains cold water with pumped hot water. You simply need a
good mains flow rate and a single impellor pump. I fitted such a system
into
my last house and it worked admirably.

In fact, even without a pressure balanced mixer, it will probably still
work
very well, but may be a little sensitive to other taps/toilets being used
in
the house.

The purists will also tell you that you should take the hot feed from a
Surrey or Essex flange installed in the hot cylinder rather than just
using
the default take-off at the top. However, you can probably get away
without
doing that - as I do.

Indeed. I fitted mine without a flange, but understood that one might be
required if it sucked air. It didn't. However, my cold tank was directly
above the cylinder with flowed bends. A 15mm tortuous feed with elbows
would
be another matter.

The best place for the pump is need the cylinder, as they prefer to push
rather than pull. It also means that the kitchen hot tap gets pumped
operation, too.

Using a pipe stat and return loop pipe on the DHW draw-off back to the
cylinder, a secondary circulation loop can be added very easily using the
same pump. The return pipe only need be very small bore plastic to thread
through joist, etc, just like cable.