"John Stumbles" wrote in message
. ..
On Fri, 05 Dec 2008 23:44:51 +0000, Grimly Curmudgeon wrote:

Indirectly, iwt - if the immersion hadn't been on all the time I suspect
the stat would have lasted longer (and he might have turned the stat up
'cos he liked a piping hot bath for nowt), but also the vent pipe
wouldn't have chalked up so much.

That bit puzzles me. Limescale typically blocks up pipes where cold fresh
water gets heated, so would be more likely to block the feed pipe to a HW
cylinder if it was hot enough throughout that the cold/hot water interface
was actually in the pipework rather than the lower regions of the cylinder
itself. The water in the vent pipe has already been heated and given up
its limescale.

And if it was oop North don't they have soft water up there anyway?

Depends on what part of oop north, some parts are very hard. They don't know
how lucky they are having soft water. They tend to use microbore pipes as
standard. I know around the Liverpool area microbore is the norm and they
all know how to fit it by rule of thumb too. The are experts at uncoiling
it. They are amazed when they see 15mm slapped in all over a house,
thinking that is something of 40 years ago.