Why does my heater have a burning smell?

Sweater weather is approaching! It will soon be getting colder, meaning it’s time to turn your heaters on and get them running again. Most people will notice a funny smell when they finally turn them on for the first time this season. Sometimes this is referred to as the “dirty socks syndrome.” Here are a few reasons why your heater may smell– but don’t fret because this is completely normal.

After heaters have been turned off for a long period of time, they collect dust and lint. This dust can collect on the heat exchanger and air ducts – so when the furnace finally turns on, the dust burns off and releases an odor. This is normal when you turn on your heater for the first time, and the smell should disappear in a few hours. In the case that it doesn’t, check your air filters because they might need to be changed.

If you notice an odor that smells similar to burning plastic or electrical parts, it may be something simple or more serious. The cause of this could be something as minor as a foreign object that starts to smell once it gets heated or even a spill that went unnoticed. This smell could also be something more serious, such as a cracked heat exchanger or an overheated furnace motor. You can inspect the heater first to try and locate the problem yourself or call an experienced technician to fix the problem.

One way to help with dirty socks syndrome is to make sure that you buy a high-quality air conditioning filters. Mildew, mold and bacteria need dust and other substances to thrive, but removing these from the air before they get into your coils is one of the key ways to prevent this.

Champion AC is here if you need to replace your heater or detect any problems and need further assistance!


Ben Hubbert is a retired Combat Controller with the United States Air Force. He started Champion AC in 2007. Ben is originally from the Mississippi Gulf Coast. He is happily married and an avid fan of the San Antonio Spurs and New Orleans Saints.