As the weather gets colder and you switch from cooling to heating your home, you may be worried about strange furnace smells in the air. Find out what the most common furnace smells mean and how proactive you should be about each one.
The Furnace Smells Musty
Musty furnace smells generally indicate mold growth someplace in the HVAC system. To avoid exposing your family to mold and mildew spores, address this problem as quickly as possible.
A clogged air filter can encourage mold, so getting rid of the smell might be as straightforward as swapping out filter. If that doesn’t work, the AC evaporator coil mounted near the furnace could be the culprit. This component gathers condensation, which can induce mold growth. You'll want a professional’s help to check and clean the evaporator coil. When all else fails, consider investing in air duct cleaning. This service cleans away hidden mold, regardless of where it's hiding in your ductwork.
The Furnace Smells Like Rotting Eggs
This is one of the most concerning furnace smells because it most likely indicates a gas leak. The utility company puts in a special substance called mercaptan to the natural gas supply to make leaks easier to notice.
If you recognize a rotten egg smell close to your furnace or out of your air ducts, shut down the heater immediately. If you remember where the main gas supply valve is located, shut that off too. Then, leave the house and contact 911, followed by your gas company. Don’t reenter the house until a professional confirms it’s safe.
The Furnace Has a Sour Stench
If you discover a sour smell that stings your nose while standing close to the furnace, this could mean the heat exchanger is cracked. This vital component safely contains combustion fumes, such as carbon monoxide, so a cracked heat exchanger could spew unsafe levels of CO gas into your home.
Carbon monoxide poisoning can be deadly, so turn off your furnace immediately if you notice a sour odor. Then, contact an HVAC professional for an inspection. Consider replacing your furnace if a cracked heat exchanger is the culprit. For your continued safety going forward, ensure you have reliable CO detectors on every floor of your home.
The Furnace Smells Dusty
When you turn on the furnace for the first time each fall, you can expect a dusty odor to fill the house for a brief moment. This is the smell of six months’ worth of dust burning away as the furnace wakes from its summer slumber. As long as the smell disperses within 24 hours, you have nothing to worry about.
The Furnace Has a Smoky Smell
Natural gas, oil and propane furnaces are combustion appliances, so they vent fumes up and out of your home. A smoky smell can mean the flue is clogged, and now fumes are backdrafting into your home. The odor might eventually reach the entire house, risking your family’s health if you let it continue. So shut down the furnace and contact a professional right away to arrange for repair.
The Furnace Smells Like Burning Plastic
Overheating and melting electrical components are the most plausible reason for a burning plastic smell to appear. A malfunctioning fan motor is another common cause. If you don’t address the problem, an electrical fire may start, or your furnace could suffer from irreparable damage. Disable the heating system as soon as possible and contact an HVAC technician for help diagnosing and repairing this weird furnace smell.
The Furnace Has an Oily Smell
If you use an oil furnace, you might pick up on this smell whenever the oil filter becomes blocked up. Try replacing it to determine if that resolves the problem. If the smell remains for more than one day after carrying out this step, it could imply an oil leak. You should get help from an HVAC professional to fix this problem.
The Furnace Reeks of Sewer Odors
Sewer gas smells pretty similar to rotting eggs, so first rule out the potential for a natural gas leak. If that’s not the source, the sewer lines might have an issue, such as a dry trap or sewer leak. Pour water down the drains, including the basement floor drain, to fill dried-up sewer traps. If the smell persists, you should contact a sewer line repair company.
Contact Levy & Son Service Experts for Furnace Repair
If you're still unsure, get in touch with an HVAC technician to check and repair your furnace. At Levy & Son Service Experts, we perform comprehensive diagnostic services to pinpoint the problem before we figure out the best solution. Then, we recommend the most viable, cost-effective repairs, alongside an up-front estimate for all options. Our ACE-certified technicians can resolve just about any heating malfunction, and we back our work with a 100% satisfaction guarantee for one year. To learn more about why your furnace smells bad or to request furnace repair near you, please contact your local Levy & Son Service Experts office today.