is it possible to add a pump to increase waterpressure & flow?

[Clive]

is it possible to add a pump to increase waterpressure & flow? similar to a shower pump for the whole house?

[Mike]

There are a couple of points that you might like to consider:

1. I do not believe that you are allowed to suck water from the mains - after all that might result in air being drawn into other people's taps.
2. Low flow rate isn't necessarily associated with low water pressure. If you have a long feed between the stopcock and your house that is small bore and perhaps furred up then the pressure might be good but the flow will be limited.

Southern Water will do a free check of the water pressure at the stopcock and at your kitchen sink. Possibly your water board will do the same. I think that they are obliged to ensure that the pressure is good at the stopcock but they are not responsible for the pipe between there and your house.

If you decide on implementing the header tank/pump scheme, I would suggest that you do go for a shower pump. They have integral switches that detect a small flow (resulting from the header tank) when you turn a tap on. This small flow activates the pump. You can also get double pumps, of course, so you could pressurise the hot as well as the cold system. Using one of these pumps would also protect you from the possibility of damage when/if the header tank empties. If this should happen the flow would cease and so the pump would switch itself off and therefore protect itself.

Mike.

[Abdullah Eyles]

I was thinking to do something like this - can you tell us how we can distinguish between the two?

Is is possible (or logical) to use a pump from a combi or similar (central heating circulation pump) - the shower pumps are a bit expensive for me (and not available here, AFAIK)

Also an idea for a low-cost pressure switch - I used an oil pressure switch as used in a car engine sump, the only problem is to keep it dry by placing it on the top of a closed vertical pipe, otherwise it rusts impressively! (and run it from 12 volt otherwise you risk shorting out the supply to earth) maybe not such a good idea after all

- flames expected!!!)

[Christian McArdle]

Exactly like a shower pump for the whole house, in fact. You may wish to distinguish between outlets, however. The pump is noisy, which isn't a problem with a shower or bath, but might wake people up if the turning on a basin tap or the washing machine rinsing at night turns on the pump.

Christian.

[Mike Barnes]

Yes, see , especially "Whole house pumps".

ObGripe: The company's called "bathstore.com" but if you put that into your browser, you get "Page not found". To get to their site you need to put "

". Doesn't give you much faith, does it?

[BigWallop]

The pressure will remain the same in any pipe connected to the supply set at

3bar and the only thing that will change is the flow rate. The only thing to happen when you increase the pipe diameter, is that the water takes longer to flow through it in accordance with the increase in volume of the pipe and would seem as though you had a reduction in the pressure, but in actual fact the water is still being supplied at 3bar.

[IMM]

tank = cold water tank. cylinder = hot water cylinder.

[The Natural Philosopher]

(i) flow ios a funcion of pressure and bore, the more of either, the bigger the flow.

(ii) adding a pumpo will work UP TO A PO*INT.

(iii) THAT POINT is when the flow hrough teh mains supply frim teh water company exceeds the pressure with which they sup[ply it, and teh dameter of their pipe.

Or to put it another way, their supply is at a certain pressure, and just e.. taking teh tap off teh mains supply and letting it gush is

*almost* as fast a flow rate as you can get. Addoung a pump can lower the pressure at your end of the pipe to (almost) 0, from 1 bar. but not any more.

So if the water mains can't do the flow rate, no amount of pumping is going to help on the suction side of the pipe. You need a pump at the water companies pumping station :-) Or a bigger pipe from them.

To put it another way. A pump can remedy deficencies in YOUR plumbing, but not the water companies...or only a bit anyway.

[BigWallop]

of page:

[IMM]

terminology convention is what I wrote above, otherwise you may confuse. Also when going to trade places it is best to know the terminology, otherwise they smell a total amateur.

[Christian McArdle]

Well it can go below zero (assuming we are relative to atmospheric pressure, not absolute zero). The problem is that negative pressure means that the company's leaky pipes start leaking in the other direction, so you get the earthy s**nk in the fresh water, rather than fresh water in the earthy s**nk. This is why you are not allowed to pump a mains supply.

Christian.

[John]

Thanks what I meant - but didnt explain very well.

Thanks

[The Natural Philosopher]

We are not.

I didn't know you weren't, but it ceertainly makes sense.

My real point was to show that there is a limit to how fast you can deliver water from a mains supply - and tanks will ultimately empty if pumped faster than replenished. Even IMM should be able to figure that one out.

[IMM]

Amazing! From someone who didn't know why you can't pump the mains.