hi
I turned my heating off 5 days ago(very wet night) and it needed resetting later that night. the flame didn't kick in for 30 minutes. all was working for 5 days. Last night was also very wet. this morning the chimney led is lit and the flame wont kick in. there was a small wet patch on top of the boiler which I can only assume has entered via the chimney. Its Christmas eve chaps, any suggestions? I am a technician by the way and are familiar with the inside of my boiler.

toolbox tony, December 2013

turned out that a little more research suggested water ingress into the differential pressure sensor. cover off, blew the pipe out and hey presto, all worked!
there is actually a little plug on the housing for clearing this but I wanted to see the issue

toolbox tony, December 2013