The Anatomy of a Furnace

Most homeowners take for granted that their furnace will keep them comfortable during the winter months. Unless there is a problem, most people don’t pay a lot of attention to the operational aspects of their furnace.

The following list gives you a basic understanding of the components that are in a typical furnace:

  • Inducer Motor – Vents the flue gases outside via a chimney or PVC pipe.
  • Pressure Switch – A pneumatic safety switch that shuts down the furnace if there is a problem with air flow, like an obstruction in the flue pipe.
  • Limit Switch – Another safety switch that shuts down the furnace if it overheats, like having a dirty filter.
  • Flame Sensor – Modern version of the old thermocouple, it verifies that a flame is present.
  • Igniter – Most function like a glow coil and when energized will ignite the gas from the burners.
  • Gas Valve – Feeds the gas to the burners.
  • Blower Motor – Delivers the heated or cooled air through the ductwork and into the various rooms of the home.
  • Heat Exchanger – The core of the furnace which allows the combustion gases to be safely vented to the outdoors; the blower motor circulates the air around the cells or sections of the heat exchanger and delivers the heat into the duct system.

All of these items are inspected and tested when we do a furnace inspection/cleaning. If any problems are detected, we will recommend replacing them to insure trouble free operation of your system.

anatomy of furnace