Can a water pump for shower run off a hot water tank?

[manda]

Hello,

I have a boiler and hot water tank. I'm getting a new shower installed with a pump. One plumber has told me that I need a new combi boiler as with a pump the hot water in the tank will get used up before the family (3 people) shower. Another plumber suggested that as the central heating heats up quickly but the hot water takes a long time the old tank is probably furred up and replacing it with a larger tank will be adaquate.

Any advice? Obviously the new tank would cost a lot less. But ultimately we all want a nice hot shower in the morning...

Thank you!

[plumbbob]

Why don't you just have the shower installed and sort the problem with the tank at a later date if it arises?

You haven't said how big the tank is so it's rather difficult to offer anything other than general guidance about installations.

So many families have mixer showers connected to standard hot water cylinders and even with four people showering, don't seem to have any problems whatsoever. Sometimes though, occasionally some do. Some have high volume showers, and like to linger under the flow - especially kids!

Try to avoid showering one after another, that will give time for the tank to recover. Morning showers tend to be quick in/outs so there is less likely to be a problem even if you do.

[chris_on_tour2002]

two factors to be borne in mind -

1) a pump will use more water for the same length of time in the shower.
2) the hot water tank has to be large enough to cope with that extra demand.

some calcs need to be done to work out if your cylinder is large enough.