Gas furnaces work on a basic principle: lit gas flames heat air that is blown through the furnace and into the rooms through ductwork. But gas furnaces are complex devices that have several safety features and mechanisms that allow them to work correctly and without creating hazards.
One of the key components for the operation of a furnace is the furnace limit switch. You don’t need to know all the details about this part, but understanding the basics will help you know more about how your furnace works—and why it sometimes doesn’t work.