If it were my decision I'd get the new main in. Who wants a lead supply, loft tanks to leak, and a pump to leak, go wrong and make a din?
Client's got a new Ferrari and a Porsche 911T in the aluminium lined garage so I reckon he could be persuaded to part with some tyre money to give his kids clean water.
I suggested the 3 options to the guy who's being paid (before I get paid for my bit - putting the Megaflo in) and he went for the pump. Ah well.
I'm not sure exactly how the switch works on say a Monsoon 3 bar. Assuming it's flow not pressure operated, if you pump into a Megaflo, the tap performance will drop off while the squashed-air store depletes, then go up again when the pump kicks in. Oooerr.
If its pressure it'll keep the tank charged of course.
Odd bits for anyone interested:
I was faced with a place with 8-10 occupants, and a 1.5 bar mains supply, and no room for a break tank. The main part of the building now has a 32mm mdpe 2 metres long from the street main (under the pavement, luckly) to the cellar where it changes to 35mm copper. The pipe passes a bath, so I pointed it in with a ff ball valve as a tap. It took several seconds for the bath to fill, off 1.5 bar. Coo.
Tried a similar thing once with a 3 bar main in 28mm in a basement - timing it to fill a bucket. The bucket hit the back wall of the basement before I'd let go of the button on the watch. The same main drops to 1.7 bar or so in the morning wash hour and by the time the main's got to the top floor, about 10 metres up, the combi up there really struggles. THere's a combi on each floor, and they have their own 22mm feeds, so though a couple of the combis aren't entirely happy, one flat doesn't affect another's drawoff because the supplies all go back to a low resistance source.
