oh wrote:

It's actually a complete re-plumbing job and it doesn't have a gravity
feed, the problem is that several sets of plumbers were in on different
stages and I didn't get in again until a couple of months after it was
all done and appeared to be working OK :-( ...

So this is a mains pressure stored hot water system then? Might have
helped if you had mentioned this in the first place!

--
Cheers,

John.

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