Nine Unusual AC Odors and What They Mean

Air conditioning is an important part of modern life, even more so during steamy summer months. When you run the air conditioner, you anticipate wonderful, cool, refreshing air to fill your home. But from time to time, AC units give off unusual or concerning odors that make you wonder if something’s wrong.

A strange smell emitting from your air conditioner or ductwork might be nothing to worry about — or it could suggest a severe problem requiring immediate attention. When in doubt, switch off the unit and contact an HVAC technician to look a little more closely. Meantime, find out about nine weird AC smells and what they might mean.

1. Rotten Eggs

A rotten egg smell could indicate a gas leak in your HVAC system. Air conditioners don’t function on natural gas, but they use the same blower and ductwork as your furnace, which could be the true root cause for this smell. If you become aware of a rotten egg smell coming from the vents, turn off your air conditioner ASAP, open the windows for fresh air and leave the house. Following that, call an HVAC contractor at once to test for a gas leak and perform the necessary repairs.

2. Musty Odors

A musty smell commonly denotes mold or mildew growing inside the AC unit or ductwork. These microorganisms flourish in damp, dark spaces, making the evaporator coil and air filter prevalent places for mold to take hold. To remove the musty smell and stop further mold growth, hire a specialist to clean your air conditioner, replace the filter and identify any other sources of moisture.

3. Tobacco Smoke

If an individual in your home smokes, odds are the AC will begin smelling like a smokey dive bar eventually. The compounding of nicotine and other chemicals inside the unit, air filter and ductwork enters into your home every time the air conditioner runs. Change the filter on a regular basis routine maintenance to help counter this AC odor. Also, it would be smart to not smoke inside the house.

4. Sewage 

If you detect a sewage smell from your HVAC system, your plumbing or sewer system could have a issue. The smell may be generated by methane gas emitting from a damaged or clogged sewer pipe or a dry drain trap, which has found its way into the ductwork. Methane is dangerous, so if you smell a sewage-like AC scent, contact a plumber at once.

5. Stinky Feet 

A filthy air conditioner with a buildup of bacteria and fungi can emit a smell reminiscent of sweaty socks. This odor may be notably strong when you switch on the AC for the first time of the season. Regular cleaning and maintenance helps to prevent this odor from occurring.

6. Skunk Smell

If you smell a skunk-like odor coming from your AC unit, there may be a decayed animal or animal feces inside the ductwork. There is the possibility that a sick or injured bird, rodent or other pest climbed inside an air duct during the winter, where it died and began decaying. This is a health hazard, so reach out to an HVAC technician to handle the problem.

7. Electrical Burning or Gun Powder

If your AC releases a burning smell, it’s possibly due to an electrical concern, such as a defective motor, circuit board, compressor or wiring. If any of these elements overheat, they may emit a burnt, gun powder-like smell. To prevent irreversible damage, turn off the AC right away and phone an HVAC technician to diagnose and correct the issue.

8. Car Exhaust

A smell identical to car exhaust could indicate a refrigerant leak. Refrigerant is the chemical your air conditioner uses to extract heat from the indoor air and exhaust it outside. A leak can be a major health and environmental hazard, so switch off your air conditioning and call for help.

9. Chemical Fumes

A chemical-like smell coming from your air vents could be attributed to surrounding vehicles, cleaning products, paints, adhesives or other substances. If your AC blower fan motor is located in the garage, even your vehicle’s idling exhaust could seep into the indoor air. These are dangerous concerns that could warrant sealing the ductwork or even redesigning your HVAC system.

Schedule Air Conditioning Repair

If you’re thinking about a weird smell arising from your air conditioner, choose Service Experts Heating & Air Conditioning for the repair you need. We use superior diagnostic equipment to promptly and accurately identify the problem. Then, we’ll explain the most cost-effective repair methods and offer recommendations to prevent a recurrence. We believe in our excellent work so much that we warrant every repair with a one-year 100% satisfaction guarantee! Phone a Service Experts office near you for additional details or to request air conditioning repair in Fort Lauderdale.