In article , Set Square wrote:
I thought that one of the features of sealed systems was that - in
the event of a leak - they should only spill a couple of litres of
water before running out of pressure. Is this not so?

A finite amount of water: initially the volume which the expansion
vessel has taken up when pressurising the system and then the rest of
the water in the system above the hole - either a steady drip, or at a
greater rate if an AAV in the boiler or elsewhere is letting air in.
But at some point it will stop whilst with a gravity system and header
tank supply not turned off the water will flow indefinitely.

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Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
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