On 02/04/2013 09:45, newshound wrote:
On 01/04/2013 23:30, John Rumm wrote:

A tale of woe for your entertainment:

http://wiki.diyfaq.org.uk/index.php?...e_rubbing_pipe



Could have been thermal movements, could also have been fretting from
small amplitude vibration in the system.

Pretty sure it was thermal - there is no vibration that you can feel or
hear in the system and it is a very long straight run of 22mm that is
fixed at the far end. Some form of galvanic action was also a possibility.

Looking at the scale deposit on the pipe, suggests that it had been
leaking for a while - but possibly at a rate where it evaporated before
causing any problems. It also occurred to me, that having relatively
recently fitted a scale inhibitor (phosphate doser) to house hot water
supply, that may have prevented scale from resealing the hole quite as
effectively.


--
Cheers,

John.

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