"yogi" wrote in message
ups.com...
I'm relocating my hot water cylinder in my bungalow to the loft near
the cold water tank. I know that the CW tank needs to be at least 1
metre higher than the showerhead, but does it also need to be higher
that the HW cylinder (or can they be positioned side by side)?


Assuming that the cold water tank is a 'normal' vented tank fed off a 'ball
valve' ....
all of the cold-water mains pressure is 'lost' once the ball-valve closes.
[that's why such systems are styled ;- 'vented']
The pressure of the water at the cold water tank's outlet will be one~two
feet high. In other words the pressure (aka 'head') is merely that of the
top water surface, The shower head needs to be at least one metre _below_
the upper surface of the cold water tank. {It's not easily achieved:if you
place the tank of the bungalow's loft floor with the shower head perhaps
one~two metres above the bungalow's floor, How high are your ceilings?
If you place the hot water cylinder side-by-side - (do you mean standing on
the same platform with their bases at the same level?) - then the hot-water
cylinder will only fill to the level of the upper-surface of the cold water
tank. Water doesn't 'fall' up-hill A moments reflection, perhaps drawing it
out on paper, should indicate to you that the bottom of the cold water tank
needs to be higher than the top-most part of the hot-water cylinder. [There
should be a expansion pipe from the upper-most part of the Hot-water
cylinder bent over to discharge into the cold water storage tank too ...
have you thought of that?]

HTH,

--

Brian