Why Your Furnace Has a Strange Smell
As the weather turns cold and you swap from cooling to heating your home, you might be worried about weird furnace smells filling the air. Learn about what the most common furnace smells could mean and how proactive you should be about them.
The Furnace Smells Musty
Musty furnace smells usually suggest mold growth somewhere in the HVAC system. To avoid exposing your family to allergy-inducing mold, handle this problem right away.
A damp air filter can harbor mold, so wiping out the smell might be as straightforward as getting a new filter. If that doesn’t work, the AC evaporator coil mounted near the furnace could be the root of the problem. This component accumulates condensation, which will sometimes trigger mold growth. You'll be better off with a professional’s help to inspect and clean the evaporator coil. When this still doesn't help, take a look at requesting air duct cleaning. This service eliminates hidden mold, regardless of where it’s growing in your ductwork.
The Furnace Smells Like Rotting Eggs
This is one of the most worrisome furnace smells since it most likely indicates a gas leak. The utility company puts in a useful substance known as mercaptan to the natural gas supply to make leaks easier to notice.
If you notice a rotten egg smell near your furnace or coming from your air ducts, shut off the heater immediately. If you know where the main gas supply valve is, shut that off too. Then, evacuate your home and call 911, in addition to your gas company. Don’t enter the house until a professional confirms it’s safe.
The Furnace Has a Sour Stench
If you detect a sour smell that stings your nose while close to the furnace, this might mean the heat exchanger is cracked. This important component houses combustion fumes, including carbon monoxide, so a cracked heat exchanger could spew unsafe levels of CO gas into your home.
Carbon monoxide poisoning can be lethal, so switch off your furnace immediately if you recognize a sour odor. Then, reach out to an HVAC professional for an inspection. Consider replacing your furnace if a cracked heat exchanger is to blame. For your continued safety going forward, see to it that you have reliable CO detectors on each floor of your home.
The Furnace Smells Dusty
When you turn on the furnace for the first time after a while, you probably expect a dusty odor to show up for a brief moment. This is the smell of six months’ worth of dust burning off as the furnace wakes from its summer slumber. As long as the smell disperses within a day, you don't have anything to worry about.
The Furnace Has a Smoky Smell
Natural gas, oil and propane furnaces are combustion appliances, so they vent fumes safely out of your home. A smoky smell will sometimes mean the flue is backed up, and now fumes are flowing back into your home. The odor might eventually reach the entire house, endangering your family’s health if you ignore it. So switch off the furnace and contact a professional right away to schedule a repair.
The Furnace Smells Like It's Burning Plastic
Overheating and melted electrical components are the most common reason for a burning plastic smell to come from your furnace. A faulty fan motor is also possible. If you don’t address the problem, an electrical fire could start, or your furnace could suffer from irreparable damage. Disable the heating system right away and contact an HVAC technician for help identifying and repairing this unpleasant furnace smell.
The Furnace Has an Oily Smell
If you have an oil furnace, you may notice this smell whenever the oil filter becomes clogged. Try replacing it to determine if that addresses the problem. If the smell persists for more than a day after taking care of this step, it could indicate an oil leak. You'll be better off with help from an HVAC expert to handle this problem.
The Furnace Smells Like Sewer Odors
Sewer gas smells very similar to rotting eggs, so first determine the possibility of a natural gas leak. If that’s not the issue, your home's sewer lines might have an issue, like a dry trap or sewer leak. Pour water down the drains, including the basement floor drain, to fill dry sewer traps. If the smell sticks around, you’ll need to contact a sewer line repair company.
Contact Stevenson Service Experts for Furnace Repair
When in doubt, get in touch with an HVAC technician to check and repair your furnace. At Stevenson Service Experts, we perform thorough diagnostic services to identify the problem before we figure out the best solution. Then, we encourage the most viable, cost-effective repairs, along with an up-front estimate for all options. Our ACE-certified technicians can handle just about any heating repair, and we back our work with a 100% satisfaction guarantee for one year. For details about why your furnace smells bad or to request furnace repair near you, please contact your local Stevenson Service Experts office today.
