Ferger wrote:
BillR secured a place in history by writing:

Modern boilers have lots of safety checks built in. Maybe one of
them was triggered?
e.g. flue seemed blocked due to string wind or high level
thermocouple tripped.



Interesting - do these things generally 'uncheck' after the problem
has gone away?
Normally yes, sometimes there is a manual reset button. This would be
documented in the boiler manual, have you got one? Installers should leave
the installation and the user instructions.
Only change in the norm I could point to is that it's rained without
stopping for almost 48 hours here.
Maybe a little of the rain got into the boiler ...