Why Your Furnace Has a Strange Smell
As the weather turns cold and you transition from cooling to heating your home, some homeowners are worried about strange furnace smells filling the air. Learn what the most common furnace smells mean and how worried you should be about them.
The Furnace Smells Musty
Musty furnace odors almost always suggest mold growth hiding in the HVAC system. To avoid exposing your family to these microorganisms, address this problem as soon as possible.
A damp air filter can harbor mold, so eliminating the smell might be as straightforward as getting a new filter. If that doesn't help, the AC evaporator coil mounted near the furnace might be the root of the problem. This component collects condensation, which could stimulate mold growth. You'll be better off with a professional’s help to check and clean the evaporator coil. When the problem still won't go away, consider requesting air duct cleaning. This service eliminates hidden mold, regardless of where it's hiding in your ventilation.
The Furnace Smells Like Rotten Eggs
This is one of the most worrisome furnace smells due to the fact that it most likely suggests a gas leak. The utility company includes a useful substance known as mercaptan to the natural gas supply to make leaks easier to detect.
If you notice a rotten egg smell around your furnace or originating from your ductwork, switch off the heater right away. If you know where the main gas supply valve is placed, shut that off also. Then, leave the house and dial 911, as well as your gas company. Don’t reenter the house until a professional can verify 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 could mean the heat exchanger has cracked. This important component safely contains combustion fumes, such as carbon monoxide, so a crack may spew unsafe levels of CO gas into your home.
Carbon monoxide poisoning could be lethal, so shut 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 to blame. For your health and safety going forward, ensure you have working CO detectors on each floor of your home.
The Furnace Smells Dusty
When you start the furnace for the first time every fall, you should expect a dusty odor to fill the house for a few minutes. This is the smell of six months’ worth of dust burning away as the furnace wakes up. As long as the smell dissipates within one day, 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 safely out of your home. A smoky smell could mean the flue is clogged, and now fumes are settling back into your home. The odor might eventually reach the entire house, jeopardizing your family’s health if you ignore it. So turn off the furnace and contact a professional as soon as you can to arrange for repair.
The Furnace Smell Resembles Burning Plastic
Overheating and melted electrical components are the most common reason for a burning plastic smell to come from your furnace. A failing fan motor is another common cause. If you don’t tackle the problem, an electrical fire might start, or your furnace could end up with irreparable damage. Shut off the heating system immediately and call an HVAC technician for help identifying and repairing this unpleasant furnace smell.
The Furnace Has an Oily Smell
If you own an oil furnace, you might notice this smell when the oil filter becomes clogged. Try replacing it to determine if that addresses the problem. If the smell remains for more than 24 hours after taking care of this step, it might imply an oil leak. You’ll need 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 eliminate the possibility of a natural gas leak. If that’s not the problem, your home's sewer lines could have an issue, such as a dry trap or sewer leak. Try pouring water down all your drains, including the basement floor drain, to fill dried-up sewer traps. If the smell sticks around, you’ll need to contact a sewer line repair company.
Contact Service Experts Heating & Air Conditioning for Furnace Repair
When in doubt, call an HVAC technician to check and repair your furnace. At Service Experts Heating & Air Conditioning, we deliver complete diagnostic services to identify the problem before we figure out the best solution. Then, we encourage the most viable, cost-effective repairs, as well as an up-front estimate for all options. Our ACE-certified technicians can handle just about any heating malfunction, 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 Service Experts Heating & Air Conditioning office today.