Apart from the day of the week, Flanders and Swann nailed it:
Here at Redfellow Cottage, the boiler ceased working. All seemed to be well, lights winking appropriately, except the damn thing wouldn’t ignite.
Send for the expert.
Nine a.m. sharp, he and his mate are on the job.
The problem stemmed from the roofers. They had dislodged débris from above, which had somehow penetrated the vent, and a fragment was preventing the boiler fan from rotating. Use of a fine bristle (actually, one of those jobs that clear out sinks) and all seems well, if not considerably improved.
What can go wrong next?
[Yes, the painter-decorator is hard at work downstairs. Doesn’t bode well.]