I had this happen IRL, when my friend was helping do some super tasks in his small apt building to get a reduction in his condo fees. The boiler needed to be reset for some reason I can't remember, so he headed down and pushed the obvious buttons that seemed to be for turning it off and on. About 30 minutes later it seemed like the apartment was getting colder and he got some calls from other people in the building. This was in the middle of a pretty cold winter, so a boiler guy had to be called to come out. It was probably 8 or 9 PM, so I'm sure he was charging some exorbitant rates to be there, and once he arrived he went around the side and pushed a tiny unmarked metal slide in and out once, which fixed the problem.