Shower pump

Shower pump is the essential element of a power shower.

There are two types of shower pump. The first is a single impeller pump, with one driving blade which pumps the water, as it is mixed, to the shower head. This means of course it must go between the mixer valve and the head. The easiest place therefore to install the single pump is in the loft as it must be above the mixer valve. This can lead to problems with the cold temperatures in the loft freezing the water and it cannot be insulated because it needs a free air flow. For this reason a twin impeller pump was introduced. This is connected to both the hot and cold water before they reach the mixer valve and can be sited, ideally, in the airing cupboard. Most pump manufacturers will specify that the pump must be within 4 metres of the hot water cylinder and at least 30mm below the cold tank. Pumps, as with power showers, must have a dedicated water supply that serves no other outlets. They must also be connected to the hot supply with an anti aeration flange such as an Essex or Warix...In general a Surrey flange should not be used as it can restrict flow to the pump inlet. An electrical connection is needed and should be taken from a switched, fused spur on a ring main outside the bathroom. It will be rated at 5 amps.