Bob Minchin wrote:

D.M. Procida wrote:
We have a cold house this morning...

The Flame LED blinks, and so does the Fan LED (which indicates a "flame
or flue fault").

We've called a plumber. In the meantime, what's the most likely fault?

Daniele

Don't always expect pinpoint accuracy from these fault lights.

In this weather I'd suspect a frozen condensate drain if you have an
external one as a prime suspect.

South Wales - we get grey skies and rain, but little in the way of
weather excitement. I checked the drain, but that's not it.

Fan motor failure can occur anytime but not common in my (limited)
experience.

The warning lights come on even if the boiler is turned on in
hot-water-only mode, before the fan spins up.

I owuldn't be surprised to discover it's the control board - which I
have previously had to replace.

If it has not had comprehensive servicing for a long time, the bottom of
the heat exchanger/sump could be full of crap.

Thanks for the advice. Hoping on a plumber now.

Daniele