Fitting shower pump

[beardieman]

I have a gasboiler with an open vented system in my house, which still works fine. I am planning to fit a shower pump (positive head)in the airing cupboard to supply water to a thermostat bath / shower tap and a seperate bathtek steam shower unit. I have seen overviews of how to connect the pump, which seem pretty straightforward except that it states that you should connect the cold water from the storage tank to the pump.
However, I think that all my taps in the house are connected to the mains, including the ones in the bathroom as the pressure is good and when I turn of the mains, the taps stop running. However on lots of plans that I have seen from manufacturers of shower pumps, the taps are connected to the cold water tank.
I suspect that i might have to open the floors up to check how the pipes run.
Would anybody be able to advise me and tell me if there is a way around as I was hoping just to connect the pump, which seems unlikely.
Thanks

 

[TicklyT]

shower pumps aren't designed to pump mains pressure water, and it's against the water regulations to do so.

Pumped hot and mains pressure cold supplies usually lead to pressure balancing problems.

If you are fitting the pump in the airing cupboard, run a cold feed from the cold water storage following the route of the cold feed to the bottom of the hot cylinder.

Take the tapping for the cold feed from below the level of the feed to the hot cylinder, so if the tank runs dry you don't get scalded.

You will probably wish to retain the cold mains feed to the basin and WC, as water from the storage tank isn't classed as potable, and flushing the WC would otherwise cause the pump to run, and they tend to be noisy - doubly so at 3AM!

 

[beardieman]

Ok. So I would have to run an extra pipe towards the shower, which should not be such a large job.

However, what should I do with the hot water supply? Will it not cause a problem if the rest of the house is going to have hot pumped water but has cold from the mains?