Can I run a combi boiler from a water tank?

[Mark300zx]

I live in a first floor flat, the mains water pressure is falling and my combi is struggling to produce decent hot water shower pressure. But my water tank gives great pressure, so could I feed the how water from the tank to the combi and cold shower water from the mains?

[pim]

Never heard of a combination boiler being fed from a cold water tank.

I stand corrected I am no plumber.

Why not have a electric shower fixed.

[Mark300zx]

I always though electric showers were meant to be slightly poop, need a combi for heating.

[DrDeAtH]

Mains booster pump may help

http://www.screwfix.com/p/salamander-pumps-homeboo...

[jagnet]

You have a combination boiler and a cold water storage cistern, in a flat? That seems to be very unlikely. Pics of said tank and boiler would help here. Apologies if i'm wrong but I suspect that all is not quite as you describe.

[Mave]

Mark300zx said:

I live in a first floor flat, the mains water pressure is falling and my combi is struggling to produce decent hot water shower pressure. But my water tank gives great pressure, so could I feed the how water from the tank to the combi and cold shower water from the mains?

I don't understand how your tank gives greater pressure than your mains - how does the mains water get up to the tank? Sounds like a flow rate rather than pressure problem- so if you feed the hot side of the shower from the tank and the cold side from the main then you won't be filling the tank and it'll drain down through the combi.

[Mark300zx]

It is a shared tank in a block of 6 flats, 2 storeys above the flat.

[Dogwatch]

Why is the mains water pressure falling? Sounds like a job for..gasp!..Managing Agent

[Mark300zx]

I think it is still within the Thames Water minimum pressure and the shower is still useable!

[Mave]

Mark300zx said:

It is a shared tank in a block of 6 flats, 2 storeys above the flat.

So how does the water get up there, if it's pressure is too low? What makes you think your mains pressure is low?

[Mark300zx]

Lower than it was, would be the correct phrase.

[Mave]

How do you know? If your water is coming out of a header tank, then what tells you that the mains pressure is lower?

[Mark300zx]

Because my kitchen cold tap has lower pressure.

Edited by Mark300zx on Tuesday 18th October 22:49

[Mave]

OK, the reason I was asking is that my shower has less flow at the moment - not because the mains pressure is lower, but because (I assume) the mains temperature is lower and so you need to turn the flow rate down to heat it to the same temperature. Same with my combi because it is controlling to a fixed outlet temperature. Having higher water pressure doesn't necessarily help if you haven't got enough power to heat it - you might just end up turning it down more!

[Mark300zx]

I have the power just not enough flow.