When your air conditioner starts putting out strange or funky aromas, it is important to take notice because it could be a sign of a significant problem. Ignoring unpleasant smells coming from your air conditioning could lead to serious damage to your air conditioning or even pose a risk to your health and safety.

Depending on the smell, the culprit might be bacteria or fungus in the system. On the other hand, it could also indicate something mechanically wrong with the AC. Some smells are a warning of an unsafe situation, including a natural gas leak.

At Air Alliance Team, we are experienced at getting to the root cause of stinky smells. If you smell something peculiar coming from your cooling system, there's a good chance our team of skilled pros has smelled it, too—and fixed it! We’ve earned our reputation as the first call for air conditioning repair in Ballwin and St. Charles.

What does a specific odor billowing out of your cooling system mean? Here are a few common air conditioner aromas and what they may mean:

Your AC Smells Like Feet

If your air conditioner smells like feet, it may be due to a buildup of bacteria or fungus inside of it. When moisture collects inside the unit, it can establish an environment that is favorable to the growth of bacteria and fungus. This can produce a bad odor that is often described as smelling like dirty feet.

Another potential explanation for the smell might be a dirty air filter. When the air filter becomes choked with dirt, dust and other contaminants, it can lead to substandard air quality and a musty smell that resembles feet.

To correct this issue, it's important to have a professional inspect and clean your air conditioning system, including the evaporator coil, drain pan and condensate drain line. It's also important to replace the air filter routinely to ensure good air quality and protect against the development of bacteria and fungus.

The Air Conditioning Smells Like Rotten Eggs

If your air conditioner smells like rotten eggs, it might be caused by 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 because of a substance added to it to make it easily detectable.

A natural gas leak is extraordinarily 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, make everyone leave 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 could be due to a collection of moisture inside the unit. When moisture accumulates inside a cooling system, it can promote the growth of mold and mildew. This can cause a musty smell that bears a resemblance to mildew.

Another possible reason for the smell may be a soiled air filter. When the air filter becomes clogged, it can lead to poor air quality and a musty smell that has a resemblance to mildew.

Annual air conditioning maintenance from Air Alliance Team can help prevent both of these issues, because a good cleaning, inspection and filter change is a very good way to keep your system operating at its best!

Your AC Smells Like Urine

One of the most distressing things is when the air coming out of your HVAC system smells like urine.

If your air conditioning smells like urine, it could be due to a variety of factors. One potential cause is a collection of bacteria or mold in the your HVAC. This can happen if moisture accumulates in the system and creates a moist environment that favorable for bacterial growth. The bacteria can create a foul odor that it similar to 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 correctly, but if the drain line becomes choked with debris, it can cause water to back up and accumulate inside the unit. This can generate a musty smell that is sometimes described as smelling of urine.

My Air Conditioner Smells Like Burning Plastic

If your air conditioning unit smells like burning plastic, this could indicate an electrical issue with the unit. After a while, the electrical elements in the air conditioning system can wear out or break, which can produce a burning smell that resembles plastic.

Another possible reason for the smell could be a foreign object lodged in the unit. If something foreign gets stuck in the air conditioning system, it can get hot and emit a smell that reminds people of burning plastic.

If you think you smell burning plastic coming from your AC unit, it’s essential to call a professional right away.

Your AC Smells Like Gas

If your air conditioning smells like gas, there could be a natural gas leak in the unit or in the surrounding area. Natural gas has a recognizable aroma, often described as smelling similar to rotten eggs or sulfur. That’s because this scent is added to natural gas so that it is easily detectable.

As stated previously, a natural gas leak can be VERY dangerous and needs immediate attention. When you suspect a gas leak, turn off your air conditioning system, open windows and doors to air out the home, leave the building and call your gas company or emergency services right away.

The Air Conditioning Smells Like Fish

Should your air conditioner smell like fish, this could be a sign of 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 cause a smell like dirty feet.

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

To correct the issue, it's important to have a professional inspect and clean your cooling system. They will be able to identify 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 numerous reasons an air conditioner smells like vinegar. One possible cause is a dirty air filter. Another likely cause of the smell may be a refrigerant leak. If the refrigerant leaks, it can make a chemical odor that is similar to vinegar.

To fix the issue, it's important to have a skilled specialist inspect and clean your air conditioning.  If the odor persists after the cleaning and exchanging the air filter, it's best to reach back out to a professional to find and repair any persistent issues with your air conditioning. Or, they can tell you if your air conditioning needs to be replaced.

If you are wanting to upgrade, Air Alliance Team can help find the ideal unit to fit your home’s needs. We deliver trustworthy, professional air conditioner installation in Ballwin and St. Charles.

The Air Conditioning Smells Like Chemicals

If the smell of chemicals is coming from your air conditioning unit, it could be due to a refrigerant leak. When the refrigerant leaks, it can create a chemical odor that is often described as smelling like chemicals or paint thinner, vinegar or acetone.

One other possible cause of the smell could be a problem with the electrical wiring or hardware inside the air conditioning system. This can result in a burning smell that resembles chemicals or burning plastic.

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

A Nasty Odor Coming from the Air Conditioning? Contact the Experts at Air Alliance Team

If your air conditioner smells nasty and you aren’t able to fix it smoothly on your own, call the cooling professionals at Air Alliance Team. We have plenty of experience working with a wide variety of AC systems. Our crew has fixed many air conditioning troubles over the years—including weird smells. Call us today for quality AC repair in Ballwin and St. Charles!