In an earlier contribution to this discussion,
Dave Liquorice wrote:

On Fri, 16 Jul 2004 20:57:38 +0100, Set Square wrote:

I would expect the steam to come out through the vent pipe and to
fill the attic with steam rather than heating the header tank snip
Am I overlooking something?

When a cylinder boils the expanding steam in the cylinder forces hot
water out of the vent pipe and thus into the header tank. Normally
making loudish thumps and bangs as it does it.


Yes, but that doesn't really explain how the whole header gets heated up to
a very high temperature.
--
Cheers,
Set Square
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