Low building water pressure problems

[nick]

I have installed a gravity fed feed hot water system in a low building with the cold water tank in the loft only 9ft above ground level) with the hot water tank at hot water tap level on the ground floor (3ft

6ins from ground) as unable to put anywhere else. Hence the top of the hot water tank is only about 1ft from the bottom of the cold water tank

- hence the gravity feed is minimal.

On top of this the building is away from civilisation so water heating is via a wood burning stove connected to the normal hot water system.

Problem is the water tank is not and cannot be directly above the hot water cylinder and I get air locks when the central heating is working causing the tap pressure to drop to zero - tap pressure is minimal anyway. Also in the middle of the night when the wood burner has gone out and the pipes have cooled the circulation pump turns off and we get bubbles blowing up through the system but the hot water tank doesnt fill up again and leaves an airlock.

I know the cause of the problem is there isnt enough head on the tank - what is the best way to solve this as I am stuck in that I cannot increase the height of the header tank or move the tank?

regards

Nick

[Dave Plowman (News)]

With very low head you need to make sure the pipework has as little flow restriction as possible. 22mm pipe instead of 15, bends rather than elbows, as few joints as possible, and make sure 'horizontal' runs if any have a slight fall.

It's quite common to have the header tank above a bathroom with a 7ft 6in ceiling and for it to work ok.

[mcbrien410]

As you are away from civilisation, is it not possible to have like a water tower, to house the cold water storage tank, outside of the living accomodation? OK it would have to be well insulated from frost etc.

Otherwise you'd seem to need pumps.

Water pressure is 0.4343 psi per VERTICAL foot.

Regards Chris.

[nick]

Thanks

What sort of pump should I be looking for. I thought this might be the solution. I'm only familiar with central heating pumps.

Nick