Why Your Furnace Has a Strange Smell
As the weather turns cold and you transition 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 could mean and how concerned you should be about them.
The Furnace Smells Musty
Musty furnace smells almost always suggest mold growth hiding in the HVAC system. To avoid exposing your family to allergy-inducing mold, handle this problem as quickly as possible.
A wet air filter can encourage mold, so wiping out the smell can be as simple as swapping out filter. If that fails to remove the smell, the AC evaporator coil placed near the furnace may be the culprit. This component gathers condensation, which could stimulate mold growth. You’ll need a professional’s help to inspect and clean the evaporator coil. When this still doesn't help, start thinking about investing in air duct cleaning. This service eliminates hidden mold, regardless of where it’s growing in your ductwork.
The Furnace Smells Like Spoiled Eggs
This is one of the most worrisome furnace smells since it frequently indicates a gas leak. The utility company puts in a particular substance known as mercaptan to the natural gas supply to make leaks easier to notice.
If you detect a rotten egg smell near your furnace or originating from your ductwork, shut down the heater immediately. If you remember where the main gas supply valve is placed, shut that off also. Then, evacuate your home and dial 911, in addition to your gas company. Don’t enter the house until a professional tells you it’s safe.
The Furnace Has a Sour Stench
If you detect a sour smell that stings your nose while standing near the furnace, this might mean the heat exchanger cracked open. This essential component houses combustion fumes, such as carbon monoxide, so a crack might pump unsafe levels of CO gas into your home.
Carbon monoxide poisoning has the potential to be deadly, so turn off your furnace as soon as possible if you notice 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 health and safety going forward, make sure 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 each fall, you probably expect a dusty odor to show up for a little while. This is the smell of six months’ worth of dust burning away as the furnace wakes up. As long as the smell dissipates within 24 hours, 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 blocked, and now fumes are settling back into your home. The odor may permeate the entire house, endangering your family’s health if you neglect it. So shut down the furnace and get in touch with a professional right away to schedule a repair.
The Furnace Smells Like It's Burning Plastic
Overheating and melting electrical components are the most likely reason for a burning plastic smell to come from your furnace. A faulty fan motor is also possible. If you don’t correct the problem, an electrical fire may start, or your furnace could experience irreparable damage. Shut off the heating system right away and contact an HVAC technician for help identifying and repairing this weird furnace smell.
The Furnace Has an Oily Smell
If you own an oil furnace, you might detect this stench if the oil filter becomes clogged. Try replacing it to see if that fixes the problem. If the smell lingers for more than 24 hours after carrying out this step, it may imply an oil leak. You'll be better off with help from an HVAC expert to handle this problem.
The Furnace Reeks of Sewer Odors
Sewer gas smells very similar to spoiled eggs, so first eliminate the potential for a natural gas leak. If that’s not the problem, the sewer lines could have an issue, like a dry trap or sewer leak. Try pouring water down the drains, including the basement floor drain, to replenish dried-out sewer traps. If the smell lingers, you should contact a sewer line repair company.
Contact Stark Services for Furnace Repair
When in doubt, call an HVAC technician to examine and repair your furnace. At Stark Services, we deliver complete diagnostic services to determine 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 each option. Our ACE-certified technicians can resolve just about any heating problem, and we back our work with a 100% satisfaction guarantee for one year. To ask questions about why your furnace smells bad or to request furnace repair near you, please contact your local Stark Services office today.