I posted about this a while ago, and the plumber came round and
diagnosed a faulty flue shroud. Water was coming out of the flue and
forming a pond underneath. The shroud has now been redesigned with a
'bubble' to force water/steam back down the flue. I still don't follow
how that volume of water could follow such a convoluted route (1m
vertical, 3m horizontal), but still.
Just been outside and seen this:
http://www.ifyoucan.org.uk/pages/Boiler.html
Obviously (?) the flue joint has failed, but this seems like a bonkers
amount of water to be ejected? I'll let the plumber know about this, but
any opinions welcome.
Rob