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What Stinks: Why Your Furnace Smells so Bad

When you get home from work, you expect a warm rush of air to welcome you, not the smell of rotten eggs or sweaty socks — but it happens. Sometimes, your heating system gives off unusual smells. Some odors dispel quickly but others are pervasive.
Here is a list of some of these odd smells and what you can do to get rid of them.

Rotten Eggs/ Sulfur: This is a really bad sign because it indicates a gas leak. Many of our home heating appliances use natural gas as fuel. As the gas is odorless, many companies add a sulfur-based chemical, mercaptan, to it, which has a distinctive, albeit unpleasant, smell to alert homeowners in case of a gas leak. If you smell this, do not try to figure out where it is coming from on your own. Evacuate your home and call a professional heating and cooling services provider to inspect your house for potential gas leakage. Contact Nelson Comfort, a locally owned and operated company, to keep your family safe.

Sweaty Socks: The overwhelmingly sour smell of dirty socks coming from your vents may be due to a bacteria and mold build-up in your heating system’s coil. During the spring and fall season, the heating coils cool down when you turn off the burners and heats up when you turn up the thermostat. This constant cooling and heating can lead to condensation, which is a breeding ground for bacteria and mold. This smell can also come from furnaces which are placed in cool and damp places. You can get rid of the smell by cleaning your air filter and heating coil with a non-acid cleaner. If the smell persists, contact an HVAC services provider.

Ozone: When electricity strikes oxygen molecules, you are left with a smell that reminds you of a thunderstorm. This odor usually occurs in our home when a wire gets overheated or burns. Over time, the blower motor in your furnace may seize up. The furnace will draw in more energy to force it to run and the excess heat buildup is often enough to melt away wires. If that happens, you will smell the distinctive chlorine-like smell of ozone. If that happens, turn off your main power switch and call a heating and cooling services provider. If left unrepaired, these wires can cause sparks and start a fire in your home.

Dust and Must: If your furnace has remained out of action for a while, it will collect dust and must. In the fall season, when you turn it up, the dust will burn up, emitting a tingly, smoky smell. However, don’t panic. This smell should dissipate in a little while. You can also prevent this smell by dusting off your furnace before lighting it up.

Smoke and Decay: These smells usually occur if your furnace’s vent or chimney becomes blocked. A blocked chimney will fail to expel smoke and vapor out of the furnace and it will circulate into your home. If a pest gets stuck into your heating system, it will give off an earthy smell of decay. In this case, you need to turn off your heating system and get your furnace, especially its vents checked.
Your nose can clue you into the fact that your furnace maintenance is overdue. If you smell any of the above odors, don’t hesitate to call Nelson Comfort and let a heating and cooling services expert assess your heating unit.

About The Author


Dan Detmer

Dan Detmer is the owner of Nelson Comfort. Dan was born into the heating and cooling industry, coming from a family of well respected HVAC contractors in Dayton, Ohio. After working in the family business, Dan decided to work for a local HVAC wholesale business helping local contractors grow their business. When he felt his heart moving him back into the residential and light commercial business, Dan joined the Mortimer Heating & Cooling team in Cincinnati, where he had called home and become part of the community for several years. After a short period of time Dan purchased the company and created what is today, Nelson Comfort. Today he operates a company based on integrity, honesty, and stellar customer service. If you have any questions feel free to tweet (at sign) NelsonComfort and we will get right back with you!

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