There is a requirement where I rent my headquarters. We must have our furnace inspected twice a year. Once when we are about to start up for the summer and the air conditioning season and then again as we start the heating season. The reason would be obvious, have a good working order HVAC plant.
But the other reason given was that it will guaranty that the furnace filter will be changed. With this note, I make sure that we have the furnace filter replaced not only then, but according to the instructions that come with the filter.
Who says that all things I do are political in nature? Ya gotta have some fun and some home improvement tips some times!