In article ,
David WE Roberts wrote:
Sounds like that's coming off the header tank.

Thanks Dave, I'd missed that when I replied earlier. The OP needs to
measure the flow rate of cold at the kitchen sink, he'll need
20litres/min to fit the Alpha CD50.

Hmmm....I'm pretty sure that the cold water is coming from the mains,
not the header tank,but I will check. If I am getting this pressure from
the header tank (around 8' head from the tank (top of water level) to
the bath tap then this is pretty impressive.

No - just means the pipe runs are well done. Remember it's 22mm pipe too.

I thought that in general cold should come from the mains (therefore
suitable for drinking),

You drink bath water? ;-)

and also there seems no point in taking cold
water from the tank as it reduces the amount available for the hot tap.

They're two separate pipe runs, and the header tank holds much more water
than the hot water cylinder.

You obviously need tank fed for applications such as a power shower where
balanced input pressures are needed.

--
*Stable Relationships Are For Horses. *

Dave Plowman London SW
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