Where to put a water pump

[ledgers]

OK, a bit of background first.. We're just in the process of putting a new bathroom in and want to get a bath tap with a deck-mounted retractable shower hose.

The trouble is, we've only got 0.2 bar pressure (we've got roughly 2m of head to the bath tap) to play with and it's been hard to find any taps at all which can cope with that.

I found one which would works, but the flow rate of 7-8L per minute seems a bit pathetic. That tap is the GEN324 from Hudson Reed (and it doesn't help that I don't know anything of their reputation for quality?)

The tap we'd like to install needs 0.5 bar (The Str8 from Pura), which means adding a water pump and HPS have recommended the Grundfos STC-1.5 C.

Then the problems start, as the Grundfos manual seems to suggest that the pump should be installed on the floor of the airing cupboard. That's a problem for two reasons: lack of space and the difficulty of cutting into the cold supply which is hidden behind the hot water cylinder.

So I'm wondering if we could install it just above the hot water tank instead? That's still almost 2m under the cold water tank in the loft.

Could that work?

I've attached a picture to illustrate!

Untitled

• ledgers
• 19 Mar 2014
• 1

(The cold feed is the pipe painted white to the right of the hot feed (centre white pipe)

 

[Newboy]

1) Shower pumps are good at 'pushing' but not 'pulling' hence the recommendation from the manufacturer to put it below the tank level.

2) You really need a dedicated hot and cold feed rather than just teeing into existing pipework - new cold water feed from the loft tank and a flange from the hot water cylinder to eliminate/reduce the possibility of air being pulled into the pipework.

 

[ledgers]

I was planning on a Surrey flange to feed an Aqualisa power shower that is also being fitted. They won't ever both be run at the same time, so presumably it's ok to use the one flange to feed both pumps (in parallel)?

Regarding the cold feed, I wasn't thinking of t-ing the connection, but pushing the main cold feed through the pump.

The idea is to pump the whole house effectively.

 

[stardanny]

It is illegal to put a pump on a main cold feed without approve from the water supplier.

Can't you run a cold feed from cold water tank to pump cold feed?

Daniel.

 

[ledgers]

Sorry, I didn't mean "mains", I just meant the main feed down from the cold tank.

 

[Norcon]

It is illegal to put a pump on a main cold feed without approve from the water supplier.

Can't you run a cold feed from cold water tank to pump cold feed?

Daniel.

The salamander home booster is legal and within water regulations and no need for any approval.

 

[xr4x4]

If your pumping hot and cold, I can't see any reason why you can't have the pump above the hot water cylinder.

As long as the pipe work and pump is below the cold water tank.

Unless the pump requires a certain amount of head I.e a minimum.

 

[ledgers]

Supply head minimum is 2m by the look of it.
http://www.plumbworld.co.uk/link/1/pwgr0033_14275_t.pdf

 

[xr4x4]

But there are many pumps that don't.