We love keeping our customers informed! And we find, most of you are just as curious too! So let’s tell you all about the inducer motor:
The history of the inducer blower/motor
First off, a furnace inducer motor is a fairly modern invention. Before Congress put minimum standards for furnace efficiency in place in 1992, there were no furnace inducer motors. It “induces” gas out of the furnace and into your flue/chimney, hence the name.
However, the most observant of you readers might be saying right now, “But that is just what the flue pipe does, and that has existed as long as furnaces have existed!” Yes, but the furnace inducer motor is a newer method of forcefully pushing these gases away. It makes your furnace perform more efficiently in a variety of ways (which is exactly why Congress mandated it all those years ago).
How a furnace inducer motor works
When your furnace first starts up, the inducer motor turns on about a minute before the burners start up. The reason for this is so the inducer blower can get rid of any gases that remained in the heat exchanger during the past heating cycle. This ensures the chamber is cleaner by the time the burners are fully ignited and the combustion process starts again. That way, the heat exchanger doesn’t become sooty and dirty! The inducer motor stays on and blows air the whole time the furnace is on, bringing in an oxygen flow, and overall improving the air quality inside the system. By doing this, it makes the system more efficient. The constant motion of the inducer motor/blower keeps the furnace burners clean as well.
What happens if the inducer motor stops working?
As you can see, this is a very important part of the furnace, cleaning air inside the furnace and keeping all the components in the furnace far cleaner than they would be with a typical “natural draft” system. (That is what existed before the inducer motor was invented. In this system, gasses would naturally drift up towards the flue, but it wasn’t nearly as efficient as using an inducer motor.)
If your inducer motor goes bad, you’ll typically be able to tell by the noise. Right after your furnace turns on for a new heating cycle, it could cause a tapping, buzzing or humming noise. However, if the inducer motor completely goes bad, your furnace will just shut off and stop working. There is a safety switch that turns off the furnace if the inducer motor is faulty. So if your furnace isn’t turning on, a bad inducer motor could be the culprit.