Fitting a shower pump All aspects of plumbing questions and answers, help, tips and information

[NeilDocherty]

I have just had a thermostatic mixer shower installed on the top floor. The cold water feed comes from a tank in the loft. The hot water comes from a large (1.5m tall) electric (Economy 7) hot water tank (fed from the tank in the loft) which is on the same floor. The pressure from both supplies is roughly the same but is not particularly high. All the feeds to the bathroom (shower, toilet and sink) run through the cupboard with the boiler.

I was thinking about fitting a twin impellor pump in the cupboard which would feed the hot and cold supplies for the bathroom but was wondering if this would work? Also, would the pump always need to be turned on for water to flow? i.e. if the pump was off, would water flow at the current pressure and only get increased when I turn it on if I was using the shower?

Any help/advice appreciated.

Neil.

[bobplum]

if the pump was installed and turned off the water flow would decrease due to resistance from the pump
if you do install a pump the feeds to pump have to be dedicated feeds to the pump and the hot would have to be first draw off so the location would be important
bob

[NeilDocherty]

Thanks for the reply.

The pump would be installed next to the hot water tank/heater which is also where the pipe from the cold water tank decends from the loft.

The only thing being bed from the cold water tank is the bathroom and the only outlet for the hot water tank is also is in the cupboard so the inlets would have a dedicated feed and would be the only thing coming out of each tank.

Do you have any idea how much water flow would drop (e.g. slightly or to a trickle) or is it very pump dependent? Also, do you know of any pumps which have a switched valve so water only flows through the pump mechanism when it's turned on? Is their some sort of pressure valve which could be fitted to the pipes so the pump could be installed in parallel with an uninterrupted pipe but would prevent back flow?

Thanks again,

Neil.

[marrtin]

Most dedicated shower pumps have integral switches which sense flow of water and so switch the pump on or off accordingly.

Considerations for fitting are sufficient cold water storage in the header tank, and ample store of hot water in the cylinder. These showers are thirsty beasts and can empty a hot water cylinder or standard header tank in 10 to 15 mins of showering.