We emphasize scheduling fall heating maintenance for a number of excellent reasons: not only does this help your heater achieve the longest lifespan possible while working at its highest energy efficiency, but it also keeps it running safely. This is especially crucial if you use a gas-powered furnace, as many homes do. Although gas furnaces are not immediately “dangerous” appliances, they can pose hazards from carbon monoxide if they don’t receive regular inspections and tune-ups.
The key component of a gas furnace that requires a professional inspection each fall is the heat exchanger.
What is the heat exchanger and what does it do?
Inside the cabinet of a furnace is a metal component that resembles clam shell. This is the heat exchanger, and it handles the job of transferring heat from the combustion gases in the furnace to the air that moves into the ventilation system. Because the hot combustion gases cannot come into contact with the air itself—you don’t want those gases sent into your home!—the heat exchanger serves as the intermediary. As the combustion gases gather inside the exchanger, they cause the metal walls to grow extremely hot. The blower fan sends air around the hot metal on the outside of the exchanger, which warms up the air flow. The cooled-down gases inside the exchanger are then safely vented out through a flue.
Why the exchanger needs inspection
Over time, a heat exchanger can develop corrosion because of the reaction between metal and the vapor in the combustion gases. Corrosion can then lead to cracks along the heat exchanger. Although these cracks are small, they will spread open when the metal expands with the heat—and this allows dangerous carbon monoxide to escape into your house. During a regular maintenance visit, your technician will examine the exchanger for signs of cracking or the corrosion that might result in cracking. Catching this allows for time to put in a new heat exchanger. In the case of very old furnaces, corrosion is often an indication that it’s time to replace the whole heating system.