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i have an electric shower that doesn't seem to be getting the volume of water it needs (6½ litres per minute as opposed to 11 litres per minute requirement as stated by the manufacturer). i was going to fit a pump onto the cold water supply from the cold water cistern but a friend tells me this is not possible and may in fact be in breach of regulation. is this true? if so, what alternative do i have for increasing the pressure apart from feeding it from the main? none, i assume...

thanks

chris

Hi Chris,
Not a plumber but regs say can't put pump on rising main, depending what system you have, maybe good idea to increase the size pipe to shower to increase water volume. Pumps in bathroom part p building regs needs to be fitted with RCB/RCCB and fused spur on own circiut need quilified sparky in.
Post your question on plumping and electrical forum some really good knowledge there.
Hope of help
KB

Using a pump assist IS a breach of regulations, but is OK from a loft header-tank source, although the tank would need to be large to avoid running dry.
It is the convention to feed electric showers direct off the rising-main, and use high KW if pressure is a bit poor. 10.5 KW units are available these days, and flow can be enhanced by using large-bore piping to feed it.

There are reputable firms supplying assist-pumps for gravity-fed showers, and that same firm also makes several pump-assisting electric showers for gravity feed from a loft tank, even up to 16 litres/min, and up 10.8 KW, but with the control available for more gentle cascade.
The brands I have in mind are "M***", and "T*****".

if your getting too much pressure you can fit a pressure regulator to save replacing all your pipework.

Link deleted, no external links allowe.

you would only fit a pump if you are getting insufficient pressure or unequal pressure.

electric showers must be run directly off your rising main and must have a check valve built into them or fitted before the shower to prevent cross contamination
your drinking water must be fed off the rising main but the other appliaces in your bathroom can be fed off your header tank.

cheers