My Puma 80e is often locking out and won't reset for hours at a time?

This seems to be more of a problem in very bad wet and windy weather.

I also have one radiator which hasn't been working for quite some time - it's the 2nd furthest away, all others are working fine although I think may be over heating a little. All CH was off but after bleeding the radiators they all came back on, except the one I've mentioned

I've lived in the property for 2 years and haven't had any servicing or maintance plans - which I plan to sort soon!

Any ideas??