Shower pump circuit All aspects of plumbing questions and answers, help, tips and information

[chazzyboy]

Evening everyone...

I wish to fit a shower pump to feed the shower/bath in my bathroom. The bathroom already has a cold feed direct from the cold storage tank in the loft, so thats good.

Is there any reason I cannot simply plumb the hot side of the twin pump into the hot boiler output, allowing pumped hot water for the rest of the house ? (There is only the single mixer shower and 1 bath)

Does it matter if the twin pump runs when your only using hot water ? ie if you run a hot tap on its own...

[ericmark]

Yes there is a good reason why not.
Except for very odd boilers like the Main 7 the water that goes through a boiler does not mix with domestic hot water there is a heat exchanger somewhere either with a hot coil in cistern or in boiler itself with combi types and combi boilers and Main 7 etc can't be connected to a shower pump.

[chazzyboy]

Thanks for your reply, not sure I explained it very well, or understand you reply, I'll try again...

The installation instructions for the pump and typical circuits show the pump T'd into the the hot water feed out the top of the boiler and then seperate feed into the bathroom for shower/bath/etc.

Is there any reason I can't take the hot water out of the top of my boiler (with the riser pipe that goes over the edge of the storage tank on the inlet side of the pump) feed that into my pump. Then the put the pump outlet back into the house hot water. Basically install the pump in the house hot water supply line, allowing all hot taps to be pressure fed.

[ericmark]

One I am not a plumber but an electrician we do cross over with some of our work. So you may get a better answer from plumber. But as I said before boilers do not heat domestic hot water directly but use some form of heat exchanger. There are a few exceptions using solid fuel but very few. So a normal pump on a central heating system does not pump domestic hot water. On larger houses and hotels one sometimes finds a system where domestic water is pumped and circulated so you don't need to run off water to get the hot through but these are normally only on larger premises.
Maybe your instructions are for a back boiler or those found in solid fuel cookers. If you look in projects Domestic Hot Water Systems you will see pictures which are easier to understand than just words you can see in the indirect cylinder how there is a coil that allows heat to transfer without the water mixing.

[ollie83]

your getting boilers and cylinders mixed up. Boiler (white and on the wall) Cylinder (copper round thing). Check with the pump manufacture and they should be able to let you know. Its all to do with flow rates etc etc. Good luck

[chazzyboy]

:oops: As soon as I pressed submit last night, I thought the same thing !! thanks for pointing that out Ollie.... If you read my post and swap the words hot water cylinder with boiler, it may read different ! sorry for leading you up the garden path....

[bobplum]

there is pumps for this kind of system
check out the projects
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