Nine Unusual AC Odors and What They Mean

Air conditioning is a necessary part of modern living, even more so during humid summer months. When you use your air conditioner, you anticipate pleasant, cool, refreshing air to fill your home. But sometimes, AC units release weird or concerning odors that make you worry if something’s wrong.

A strange smell generating from your AC unit or ductwork might be no big deal — or it could suggest a severe problem necessitating prompt attention. When in doubt, switch off the unit and call an HVAC technician to check it out. Right now, learn about nine weird AC smells and what they might mean.

1. Rotten Eggs

A rotten egg smell could suggest a gas leak in your HVAC system. Air conditioners don’t operate on natural gas, but they share a blower and ductwork with gas-fired furnaces, which could be the true reason for this smell. If you notice a rotten egg smell emitting from the vents, turn off your air conditioner ASAP, open the windows for venting and leave the house. Following that, call an HVAC contractor at once to check for a gas leak and perform the necessary repairs.

2. Musty Odors

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

3. Cigarette Smoke

If a person in your home smokes, odds are the AC will start smelling like a dirty ashtray before long. The accumulation of nicotine and other chemicals inside the unit, air filter and ductwork circulates into your home every time the air conditioner runs. Change the filter plan routine maintenance to help prevent this AC odor. Also, it would be wise to not smoke inside the house.

4. Sewage 

If you notice a sewage smell from your air conditioner, your plumbing or sewer system is likely to be the problem. The smell may be generated by methane gas emitting from a broken or blocked sewer pipe or a dry drain trap, which has made its way into the ductwork. Methane is dangerous, so if you smell a sewage-like AC odor, contact a plumber without delay.

5. Stinky Feet 

A dirty air conditioner with a buildup of bacteria and fungi can emit a smell similar to that of dirty socks. This odor may be notably strong when you start up the AC for the first time in several months. Regular cleaning and maintenance helps prevent this odor from happening.

6. Skunk Smell

If you smell a skunk-like odor coming from your AC unit, there may be a dead animal or animal waste 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 decomposing. 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 likely due to an electrical concern, such as a damaged 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 immediately and contact an HVAC technician to diagnose and fix the issue.

8. Car Exhaust

A smell identical to car exhaust could signify 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 serious health and environmental hazard, so turn off your cooling system and call for help.

9. Chemical Fumes

A chemical-like smell coming from your air vents could be traced to surrounding vehicles, cleaning products, paints, adhesives or other toxins. If your AC blower fan motor is located in the garage, even a car’s idling exhaust could mingle with the indoor air. These are grave concerns that could warrant sealing the ductwork or even redesigning your HVAC system.

Schedule Air Conditioning Repair

If you’re worried about a weird smell coming from your air conditioner, rely on Service Experts Heating & Air Conditioning for the repair you need. We use advanced diagnostic equipment to quickly and accurately define the problem. Then, we’ll share the most cost-effective repair methods and present recommendations to prevent a recurrence. We believe in our exceptional 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.

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