Thank you "raden" but everyone on this site, indeed in the whole of W
Europe, knows that the Potterton Envoy is a dog. Observations about
"bears in woods " and "Is the Pope a ..." come to mind.

But if I don't want to spend the £1400 or so to replace (add £1000
for BG), it seemed a good idea to get it fixed for the moment. So, the
£16 spent on the PCB was wasted but thinking it thru' got it fixed.
(It foxed BG)

Chatting to a mate, he came up with the question,
"If you had to choose between an very intelligent but un-trained person
or a stupid person who had been trained, what's your choice?" NO
contest!

The CORGI ******* from BG have now, over the last couple of years, to
my reckoning:

- omitted to screw back the fan unit on the bottom of the boiler,
allowing Gas/air to leak into the boiler's case,
thus risking a pretty good explosion,

- forgotten to re-connect the gaiter on the flue allowing nasty CO
and other stuff to leak,

- and, now swapped and didn't find the thermistor wires problem.

How can I know that any allegedly qualified, i.e. CORGI person is any
better?

I think it was Bernard Shaw who said, "All professions are a
conspiracies against the layman". And we though we was lawyers he was
after!

It's still true about the newer "experts".

I'll buy a new boiler in the Spring, put it in myself and F*** the
so-called pros. Wait a year or so and get it inspected and onto
someone's maintenance program. Since I can do it safely, I know it
will be OK.

"Who installed this?", I will be asked. "No idea", I will reply, "just
moved in".
"Looks OK", will come the reply, "happy to put it on contract".

Naffer