Why Does My Furnace Smell Bad?

It’s that time of the year again when everyone is cranking on their furnace for that incoming fall and winter weather. If your furnace smells strange or irregular, don’t tell yourself that it’s nothing and ignore it. While furnaces normally do a great job of keeping Georgia homeowners cozy during the long, hard winters, occasionally a furnace develops problems over time. With that being said, a distinctive odor can give you a better idea of what may be the problem with your furnace. To ensure the safety of your family, Fritts Heating & Air discusses some of the most common smells a furnace makes and the causes behind them.

furnace smell

Rotten Eggs or Sulfur Smell

Natural gas is highly flammable and makes for a good fuel source for appliances throughout your home. Unfortunately, natural gas can also be dangerous when inhaled. It can lead to dizziness, nausea, fatigue, and even irregular breathing. As natural gas has no odor of its own, many gas companies add the chemical mercaptan as a safety precaution. This sulfur-based chemical gives off the distinct smell of rotten eggs so homeowners know when natural gas is present. If you have a propane or gas-powered furnace that smells like rotten eggs or sulfur, you may have a gas leak. If you suspect a gas leak in your home, remove all open flames and call your local gas supplier ASAP. This is to be taken very seriously and fixed as soon as possible as an open gas leak can lead to potential health risks and/or death.

Locker Room Furnace Smell

We’ve all been in a locker room and know that distinct smell. With that being said, you never expect that smell to come from your furnace. A locker room furnace smell occurs when bacteria build up on your heating system coils. During the spring and fall seasons, the coils cool with outdoor temperature drops and reheat when you turn up the thermostat. This constant cycle between warm and cold often results in condensation buildup which results in bacterial growth. The best way to eliminate this bad odor is from a simple cleaning. Start by replacing your unit’s air filter and by cleaning the evaporator coils. If the smell sticks around, contact your HVAC technician to discuss cleaning your air ducts and the rest of your unit.

Electrical Burning Smell

When a furnace overheats it creates an electrical or metallic smell. As your furnace ages, worn bearings cause the blower motor to seize up or stop. Your furnace may then draw additional electricity to push through the resistance, and that additional voltage may result in excessive heat buildup in the motor. The heat is often enough to melt away wire insulation. In turn, your unit could produce electrical shorts and sparks that emit the electrical burning smell. If left alone, these sparks and melting wires create enough heat to start a fire in your home. If you smell electrical burning, cut the power to your unit and call your local HVAC company for service.

Burning Smoke or Oil Smell

Your furnace could create a smoky or burning oil smell for a variety of reasons:

  • If you store items close to the pilot light. These items could catch fire or melt, resulting in the smell of smoke and/or burning plastic.
  • If you have an oil furnace, your unit might not ignite all the oil. Instead, the oil creates a fog that smells much like an engine. If that fog ignites, it could result in a large flame and excessive smoke.
  • If you filled the oil tank, any spillage may give off an odor as it dissipates. This smell should fade after a day or two. But if it continues to smell, you may have an oil leak. Get this checked ASAP.

Dust or Musty Smell

When you haven’t used your furnace for a while, your furnace might give off a dusty or musty smell when turned on. The odor may smell particularly strong for the first few uses of the season, and then it may fade gradually. This smell occurs when dust, dirt, and other debris collect on your unit and in your air ducts. As your furnace warms, the dust and dirt may burn away and smell faintly of smoke. Though the smell may seem worrisome, you don’t have to panic about damage to your unit. However, if the smell persists, you could have a clogged filter that allows dust and dirt to reach your motor. Check and replace your air filter as needed.

Does Your Furnace Smell? Call Fritts Heat & Air Today!

At Fritts Heat & Air, we’re not comfortable until you are. That means keeping you warm during the winter months and providing you with prompt and professional heating system repair services when you need us. We repair all brands of residential and commercial heating systems. Let us keep your home or business warm with our expert heating system repair services. When you first notice that your furnace is not working or keeping your home or business warm appropriately, it’s best to call the furnace repair experts at Fritts Heat & Air. Our highly trained HVAC technicians will inspect, service, and repair your heating unit. We offer our customers more than two decades of experience within the HVAC industry. We work fast, efficiently, and affordably. We also have HVAC financing options available.