Thanks all,

Corgi block came yesterday, removed burner assembly and scrubbed away a
ton of crud. Did a lot of work with the hoover on that and inside the
boiler casing. Add to this, he added a 900mm extension and bracketting
to the vertical flue (all now stands proud 1m above the building), and
he made me improve the ventilation (fitting an ouside air brick and
partition door vents) so that the boiler has better oxygen at the burners.

He reckons about 10 years at least left in the Potterton Kingfisher
beast, and I'm happy with that. Cost of work was about £300 which
although steep for my finances and not quite in the DIY spendthrift
ethic compares with experts that sort out my neglected car every time it
gets the MOT fail certificate. It's a lot less than to start paying for
installation of a new boiler at the moment, even bearing in mind the
projected efficiency of a replacement.

A yearly service from this bloke would cost about £60, and his contact
number is now close at hand - having gone through so many friends for
recommendations to find most gas fitters very busy or not checking their
voicemail. I should give up software writing and become a fitter myself.

Great to have a decent bath again :-)

--
Adrian C