Nine Unusual AC Odors and What They Mean

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

A strange smell emitting from your cooling system or ductwork might be no big deal — or it could signal a severe problem necessitating prompt attention. When you have concerns, turn off the unit and contact an HVAC technician to check it out. In the 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 operate on natural gas, but they utilize the same ductwork and blower that your furnace uses, which could be the true reason for this smell. If you notice a rotten egg smell coming from the vents, turn off your air conditioner immediately, open the windows for ventilation and evacuate the house. Following that, call an HVAC contractor promptly to inspect for a gas leak and conduct the necessary repairs.

2. Musty Odors

A musty smell normally means mold or mildew growing inside the AC unit or ductwork. These microorganisms thrive in damp, dark spaces, making the evaporator coil and air filter likely places for mold to set in. To deal with the musty smell and deter further mold growth, hire a professional to clean your air conditioner, replace the filter and determine any other sources of moisture.

3. Tobacco Smoke

If an individual in your home smokes, odds are the AC will begin smelling like a dirty ashtray before long. The compounding of nicotine and other chemicals inside the unit, air filter and ductwork spreads into your home every time the air conditioner turns on. Change the filter arrange for routine maintenance to help counter this AC odor. Also, it would be smart to not smoke inside the house.

4. Sewage 

If you notice a sewage smell from your AC unit, your plumbing or sewer system may actually be the problem. The smell may be caused by methane gas emitting from a busted or plugged sewer pipe or a dry drain trap, which has made its way into the ductwork. Methane is unhealthy, so if you smell a sewage-like AC odor, contact a plumber immediately.

5. Stinky Feet 

A filthy air conditioner with a buildup of bacteria and fungi can emit a smell similar to that of dirty socks. This odor may be especially strong when you start up the AC for the first time of the season. Regular cleaning and maintenance aids 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. It’s not uncommon to find that a sick or injured bird, rodent or other pest climbed inside an air duct over the winter, where it died and began rotting. This is a health hazard, so contact an HVAC technician to tackle the problem.

7. Electrical Burning or Gun Powder

If your AC produces a burning smell, it’s likely due to an electrical issue, such as a damaged motor, circuit board, compressor or wiring. If any of these parts overheat, they may emit a burnt, gun powder-like smell. To reduce the risk of permanent damage, turn off the AC right away and get in touch with an HVAC technician to diagnose and remedy the issue.

8. Car Exhaust

A smell comparable to car exhaust could imply 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 power down your air conditioner and call for help.

9. Chemical Fumes

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

Schedule Air Conditioning Repair

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