Why is it that the central heating waits until it's really cold before breaking down? (Okay, you Scandinavian types, I know circa freezing isn't really cold in your parts, but it's cold enough.) The signs were there when it shut down one night with a dramatic fading wail, like the dilithium crystals giving way on Star Trek, then gave off a series of loud bangs and clonks in the pipes that made it seem we were under heavy attack by militant plumbers.
After waking to cold radiators and a baleful red light on the control panel, several resets later it is running, but seems to be very confused about when it's hot enough, cutting out every few minutes when the radiators are only lukewarm. To make matters worse, it's now intermittant - it can suddenly remember how to work for an hour or two, then give up again. This means, inevitably, that when the boiler man comes tomorrow morning it will purr away and behave perfectly. Oh, joy.