In message 2UKkc.18$XV3.1@newsfe1-win,
"Franglais" wrote:

We would like to install an electric power shower in our bathroom. The
location is on the wall of the cupboard where the hot water tank resides
with pipes right behind the wall and high wattage electric to the immersion
heater.

Would this be a major plumbing job? DIY able? If we got a Plumber in what
would the ball aprk cost be?


Do you mean a pumped shower (i.e. using stored hot water), or an
electrically heated shower?

Electrically speaking, in either case you will not be able to use the
supply to the immersion heater in order to feed the shower. The
immersion should be powered from its own circuit, probably be fused at
15A or 16A for a heater rated at perhaps 13A (3kW). In theory this would
allow you to attach a small load such as a shower pump, but the IEE
doesn't like it and specifically says that fixed heaters such as
immersions should be supplied from their own dedicated circuits. The
supply to a pump is quite small however and can quite properly be taken
from a spur on your sockets circuit.

If you mean an electrically heated shower then these take a *lot* more
power than an immersion heater and are fed from their own dedicated
circuit, usually rated between 30A (7kW) and 45A (10kW). They must also
be fed via an RCD.

In the case of a shower pump, the electrical work is relatively easy and
probably quite minor assuming the ring circuit isn't too far away from
the location of the pump. In the case of an electrically heated shower
the need to run a hefty bit of cable (6mmsq or 10mmsq) and to provide a
suitable supply will make the electrical work much more onerous.

As for the plumbing, electrically heated showers just need a good cold
feed. Pumped showers may need a bit more, but plumbing isn't my strong
point. There have been several threads here *very* recently (in the last
fortnight or so) containing advice on this issue - search for "essex
flange" and you should turn up several interesting discussions.

HTH

Hwyl!

M.

--
Martin Angove: http://www.tridwr.demon.co.uk/
Two free issues: http://www.livtech.co.uk/ Living With Technology
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