Shower pump location

[Davidgpa]

I wish to fit a pump to increase hot & cold pressure to my bathroom. Manufacturers say the pump should be near the hot tank but there is no room. Does it matter if I install it on the floor in a cupboard in the bathroom ? The height of the inlet water pipes would be virtually the same as if it was fitted in the airing cupboard.

 

[hi-spec plumbing heating]

you can fit the pump where you like.

 

[Softus]

It's better to install the pump such that the resistance to flow is greater in the pipework after the pump than in the pipework before it.

The aim of this is to reduce the risk of cavitation. This is why manufacturers recommend siting the pump close to the source of the hot water.

 

[Davidgpa]

Thank you. A plumber advised me that it MUST go next to the hot tank so it could push, not pull, the water. This is the manufacturers recommendation, though I don't understand why.

 

[chrishutt]

The main point is that the pump should be at a lowish level, e.g. the level of the base of the cylinder, to ensure that the static pressure remains quite high and suppresses cavitation. The pump needn't be all that close to the cylinder horizontally provided the supply pipes to the pump are large enough to reduce resistance to flow (typically 22mm).

Cavitation occurs if the pressure at the pump impeller is too low, which might be due to low static pressure and/or low dynamic pressure due to pipework resistance. If that doesn't make any sense to you, just follow the instructions.

 

[Davidgpa]

Gentlemen, thank you, all my queries have been answered.