When your air conditioner starts spewing weird or unappealing odors, it is necessary to take notice because it could be a sign of a big problem. Ignoring unpleasant smells coming from your air conditioner could lead to serious damage to your HVAC system or even pose a risk to your health and safety.

Depending on the cause of the odor, the cause could be bacteria or fungus in the system. Other times, it could also signal something mechanically wrong with the AC. Some smells are even indicative of a dangerous problem, like a natural gas leak.

At ACS Heating and Air Conditioning, we are skilled at diagnosing and fixing these type of problems. If you smell something odd coming from your cooling system, you can bet that our team of talented specialists has smelled it, too—and fixed it! We’ve earned a reputation as the go-to team for air conditioning repair in Tucker.

What does a certain smell coming coming from your AC mean? Here are a few typical air conditioner odors and what they might mean:

My Air Conditioner Smells Like Feet

If your air conditioner smells like feet, it can be because of a buildup of bacteria or fungus in the unit. When moisture collects inside the unit, it can create an environment that is beneficial to the development of bacteria and fungus. This can cause a nasty odor that is often described as smelling like feet.

Another likely explanation for an odor of stinky feet may be a dirty air filter. When the air filter becomes clogged with dirt, dust and other contaminants, it can lead to low air quality and a musty smell that it similar to the smell of feet.

To solve this dilemma, it's important to have an experienced specialist inspect and clean your air conditioning system, including the evaporator coil, drain pan and condensate drain line. It's also important to change the air filter regularly to provide good air quality and prevent the development of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your stinks like rotten eggs, it might be due to a natural gas leak in the unit or in the surrounding area. Natural gas has a distinctive odor, often described as smelling like rotten eggs or sulfur, that is added to it to make it easily detectable.

A natural gas leak is a situation that is very dangerous and requires immediate attention. If you suspect a gas leak, turn off your air conditioning system, immediately open windows and doors to air out the area, evacuate the building and call your gas company or emergency services at once.

My Air Conditioner Smells Like Mildew

If your cooling system smells like mildew, it might be due to a accumulation of moisture inside the unit. When moisture accumulates inside an air conditioner, it can foster the growth of mold and mildew. This can cause a musty stench that resembles mildew.

Another possible explanation for the smell may be a dirty air filter. Once the air filter becomes clogged, it can lead to poor air quality and a musty smell that resembles mildew.

Annual air conditioning maintenance from ACS Heating and Air Conditioning can help prevent both of these situations, because a good cleaning, inspection and filter change is a terrific way to keep your system running at its best!

My Air Conditioner Smells Like Urine

One of the most distressing things is when an air conditioner smells like urine.

If your air conditioner smells like urine, it could could be caused by multiple factors. One likely cause is a accumulation of bacteria or mold in the your HVAC. This can happen if moisture accumulates in the system and creates a damp environment that can promote bacterial growth. The bacteria can produce a foul odor that is like urine.

Another feasible cause of the scent of urine could be a clogged drain line. The condensation that forms inside the air conditioning unit needs to drain away properly, but if the drain line becomes choked with debris, it can cause water to back up and accumulate inside the unit. This can create a musty smell that is sometimes described as smelling of urine.

My Air Conditioner Smells Like Burning Plastic

If your air conditioning system smells like burning plastic, it might be because of an electrical issue with the unit. After a while, the electrical parts in the air conditioning system can wear out or bust, which can create a burning smell that resembles plastic.

Another possible root cause of the smell could be a foreign object stuck in the HVAC system. If something foreign gets stuck in the air conditioning system, it can become hot and cause a smell that reminds people of burning plastic.

If you smell burning plastic coming from your air conditioner, it’s important to contact a professional right away.

My Air Conditioner Smells Like Gas

If your air conditioning smells like gas, it could be because of a natural gas leak in the unit or in the surrounding area. Natural gas has a recognizable smell, often described as smelling like rotten eggs or sulfur. That’s because an odor is put into natural gas so that it is easily detectable.

As mentioned previously, a natural gas leak can be VERY hazardous and requires immediate attention. When you suspect a gas leak, turn off your air conditioning system, open windows and doors to air out the home, evacuate the building and contact your gas company or emergency services right away.

Why My Air Conditioner Smells Like Fish

When your air conditioner smell like fish, you may have a situation where there's a build-up of bacteria or mold in the unit. Moisture causes an environment that promotes the growth of bacteria and mold. This can cause a strong odor that is sometimes described as smelling like fish or, as mentioned earlier, it also can create a smell like dirty feet.

Another potential cause of the smell could be a dead animal or other biological material caught inside the air conditioning system. This often can take place if an animal such as a mouse or bird is trapped inside the unit and dies.

To correct the issue, it's often necessary to have a professional inspect and clean your air conditioning system. They will be able to determine the source of the smell and take the correct steps to remove any contaminants and prevent the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be multiple reasons a home's air conditioning system smells like vinegar. One possible cause is a clogged air filter. One other likely cause of the smell might be a refrigerant leak. When the refrigerant leaks, it can create a chemical odor that is described as smelling of vinegar.

To fix the issue, it's beneficial to have a skilled mechanic examine and clean your air conditioning.  If the odor persists after the cleaning and changing of the air filter, it's best to reach back out to a professional to diagnose and repair any underlying issues with your air conditioning. Or, the tech can tell you if your air conditioning should be replaced.

If you are planning to upgrade, ACS Heating and Air Conditioning can help select the correct unit to fit your home’s needs. We deliver dependable, professional air conditioner installation in Tucker.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioner, it could be the result of a refrigerant leak. When the refrigerant leaks, it can create a chemical odor that people sometimes describe as smelling like chemicals or paint thinner, vinegar or acetone.

One other possible reason for the smell could be something wrong with the electrical wiring or elements inside the air conditioning system. This can result in a burning smell that resembles chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical problem, it's important to shut down your air conditioning system right away and contact a professional to inspect and repair the unit. Refrigerant leaks can be dangerous and may require immediate attention to avoid injury or damage to your house.

Strange Smell Coming from Your AC? Call the Pros at ACS Heating and Air Conditioning

If your air conditioner smells nasty and you aren’t able to fix it simply on your own, reach out to the cooling experts at ACS Heating and Air Conditioning. We have plenty of experience working with a wide variety of air conditioning systems. Our crew has fixed countless air conditioning problems throughout the years—including funky smells. Call us today for quality AC repair in Tucker!