When your air conditioner starts emitting unusual or gross odors, it is important to take notice because it could be a sign of a big problem. Dismissing unpleasant smells coming from your air conditioning could lead to further damage to your air conditioning or even pose a risk to your health and safety.

Depending on the cause of the odor, the root of the problem might be bacteria or fungus in the system. On the other hand, it could also signal something mechanically wrong with the AC. Some smells are even indicative of a dangerous scenario, such as a natural gas leak.

At Halverson Brothers Inc, we are skilled at diagnosing and fixing these type of problems. If you smell something peculiar coming from your air conditioner, there's a good chance our team of qualified pros has smelled it, too—and fixed it! We’ve earned a reputation as the premier company for air conditioning repair in Menomonie and western Wisconsin.

What does a particular smell wafting out of your cooling system mean? Here are some frequent air conditioner odors and what they may mean:

My Air Conditioner Smells Like Feet

If your air conditioner smells like feet, it may be caused by a buildup of bacteria or fungus inside of it. When moisture collects inside the unit, it can produce an environment that is favorable to the spread of bacteria and fungus. This can cause a foul odor that is often described as smelling like stinky feet.

Another possible explanation for an odor of stinky feet could be a dirty air filter. If an air filter becomes choked with dirt, dust and other debris, it can result in poor air quality and a musty smell that it similar to the smell of feet.

To fix this issue, it's important to have a quality service tech inspect and clean your air conditioning system, including the evaporator coil, drain pan and condensate drain line. It's also important to exchange the air filter on a regular basis to ensure good air quality and protect against the formation of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioning unit reeks of rotten eggs, it might be the result of a natural gas leak in the unit or in the surrounding area. Natural gas has a recognizable odor, often described as smelling like rotten eggs or sulfur, which is added to it to make it easily detectable.

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

My Air Conditioner Smells Like Mildew

If your AC is giving off an odor like mildew, it may be due to a accumulation of moisture inside the unit. When moisture collects inside a cooling system, it can promote the growth of mold and mildew. This can cause a musty odor that resembles mildew.

Another possible cause of 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.

Routine air conditioning maintenance from Halverson Brothers Inc can help avoid both of these problems, because a good cleaning, inspection and filter change is a very good 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 conditioning smells like urine, it could be traced back to a number of things. One likely cause is a collection of bacteria or mold in the air conditioning system. This can happen when moisture accumulates in the system and creates a wet environment that can promote bacterial growth. The bacteria can emit a foul odor that is like urine.

Another feasible cause of the stink could be a clogged drain line. The condensation that forms inside the air conditioning unit needs to drain away effectively, 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 AC smells like burning plastic, it might be because of an electrical problem with the unit. After some time, the electrical components in the air conditioning system can wear out or break, which can make a burning smell that resembles plastic.

Another possible 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 heat up and emit a smell similar to burning plastic.

If you think you smell burning plastic coming from your AC unit, 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 your home. Natural gas has a recognizable aroma, often described as smelling similar to rotten eggs or sulfur. That’s because this scent is incorporated into natural gas to make it easily detectable.

As mentioned previously, a natural gas leak can be VERY harmful and calls for immediate attention. If you suspect a gas leak, turn off your air conditioning system, open windows and doors to air out the home, get everyone out of 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, it could be due to a build-up of bacteria or mold in the unit. Moisture creates an environment that is conducive to the growth of bacteria and mold. This can cause a foul odor that can be described as smelling like fish or, as mentioned earlier, it also can create a smell like dirty feet.

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

To fix the issue, it's important to have a professional examine and clean your air conditioning system. They will be able to determine the source of the smell and take the appropriate steps to remove any contaminants and keep the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be several reasons your air conditioning system smells like vinegar. One possible cause of the smell could be a dirty air filter. Another possible cause of the smell may be a refrigerant leak. When the refrigerant leaks, it can generate a chemical odor that resembles vinegar.

To fix the issue, it's essential to have a skilled specialist inspect and clean your air conditioning.  If the odor persists after the cleaning and replacing of the air filter, it's best to reach back out to a professional to identify and repair any hidden issues with your air conditioning. Or, the tech can tell you if your air conditioning needs to be replaced.

If you are planning to upgrade, Halverson Brothers Inc can help find the ideal unit to fit your home’s needs. We deliver dependable, expert air conditioner installation in Menomonie and western Wisconsin.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning equipment, it could be due to a refrigerant leak. If the refrigerant leaks, it can create a chemical scent that some people describe as smelling like chemicals or paint thinner, vinegar or acetone.

An additional possible source of the smell could be a problem with the electrical wiring or parts inside the air conditioning system. This can produce a burning smell that it similar to chemicals or burning plastic.

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

Strange Smell Coming from Your AC? Call the Pros at Halverson Brothers Inc

If your air conditioner smells nasty and you aren’t able to fix it simply on your own, reach out to the cooling specialists at Halverson Brothers Inc. We have plenty of experience working with a wide variety of cooling systems. Our crew has fixed many air conditioning concerns throughout the years—including strange smells. Call us today for quality AC repair in Menomonie and western Wisconsin!