Smells like rotten eggs, burning electrical, or chemicals coming from your furnace should never be ignored, because they could be signs of a serious or even dangerous problem. While it’s normal to notice a dusty burning smell the first time a furnace runs in the winter, if the odor continues, it should also be checked out by a professional.
Rotten Egg Smell
The most obvious and serious odor you may notice from your furnace is the rotten egg smell that indicates a gas leak. Many natural gas suppliers add Sulphur to the gas to make leaks easier for people to detect without equipment. This is a dangerous situation, so if you notice a rotten egg smell coming from your furnace, open windows to let in fresh air, evacuate the home, and call your local gas company and/or 911 to report the leak.
Burning Electrical Smell
If you notice a smell like burning wires or an overheated motor, it could be a sign that the blower motor on your furnace is seizing up. This can happen because of worn bearings, and will often cause the motor to overheat, use too much voltage, and even melt the wires attached to it. In the case of a burning electrical smell throughout the house, use your thermostat to shut off the furnace and then call a licensed HVAC technician to inspect the system.
A chemical odor like formaldehyde could be a sign of a cracked heat exchanger. This is another serious problem, because it can allow carbon monoxide gas to circulate through your home’s ductwork. Carbon monoxide detectors should be installed on every level of a home, especially near the furnace, because the gas is odorless and colorless. If you notice a chemical smell coming from your furnace, call a professional to inspect the unit as soon as possible.
Dusty Burning Smell
A dusty burning smell when you first turn on your furnace for the season is common, and usually nothing to worry about. Dust and dirt accumulates during the summer while the unit is off, and the smell will usually go away a few hours after the furnace starts back up.
If the smell lingers, try changing the furnace filters; if that doesn’t get rid of the dusty burning smell, it’s time to call for service. It could just be that your furnace needs a deeper cleaning, or there could be a more serious issue. Either way, it’s best to play it safe and have a professional take a look.
In the Wichita area, call Reddi HVAC at 316-462-2572 for furnace tune-ups, service and replacement.