Well mine was off this morning (at 4:45am when I got up for the usual trip to the loo!) 3c outside and 13c inside!
New boiler had gone off again, did the same during the last cold snap. Luckily I know what it is, the water pressure drops!. Problem was finding instructions on how to top it back up!.
99% of Baxi’s information sheets/videos show the usual mechanical circular pressure gauge with a needle that moves, mine only has a digital display with error codes written in ancient Greek or something similar!. I eventually found a video that was close enough and managed with that, pressure now at 1.6 bar and boiler back on.
Please excuse spelling/typos. Apart from being a clot it turns out I had one on my cerebellum that's now causing various problems!