pump whole house, gravity system

[lazyade]

I'm writing on behalf on a mate who has a gravity fed hot water system and wants to increase the hot tap pressure throughout the house. The hot water is currently only at head pressure and the bathroom cold supply is also from the cold header tank.

What we're considering doing is fitting a twin head 1.5 bar pump to the feed from the cold water tank and also from the hot water cylinder. Question is will it be ok to install the pump in the loft, or should it be installed in the airing cupboard? I know there needs to be head pressure for the pump to work, but is it the outlet of the water that matters (ie the taps) or where the pump is situated? In the loft the pump itself will only be about 20 cm below the cold water header tank feeding the hot water cylinder. I think this will be ok as the take off from the pump will be in the bathroom below or the kitchen. Will I be ok to install the pump in the loft?

Cheers.

 

[simond]

You must follow the pump manufacturer recommendations, they will all give a minimum 'head' from the cold water storage tank. Ignore it and you will not be covered when it goes t'ts up. That is why many shower pumps are sited in the airing cupboard, to achieve the manufacturer recommended head.

If the taps are sited above the cold water storage tank, you need a negative head pump, once again, follow the instructions to the letter.

Personally, I would not have a shower pump in the house.

 

[lazyade]

Cheers Simond, the tap take offs are below the header tank, at least 2 metres.