When your air conditioner starts emitting strange or gross odors, it is a good idea to take notice because it could be a sign of a significant problem. Dismissing unpleasant smells coming from your air conditioning could lead to further damage to your AC 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. Other times, it could also signal something mechanically wrong with the AC. Some smells are even indicative of a harmful problem, such as a natural gas leak.

At Kilbourne Heating & AC, we have a nose for these sorts of things. If you smell something peculiar coming from your air conditioner, you can bet that our team of skilled specialists has smelled it, too—and fixed it! We’ve earned our reputation as the go-to team for air conditioning repair in Delray Beach.

What does a specific odor billowing coming from your AC mean? Here are a few common air conditioner smells and what they may mean:

My Air Conditioner Smells Like Feet

If your air conditioner smells like feet, it could be caused by a buildup of bacteria or fungus in the unit. When moisture accumulates inside the unit, it can create an environment that is favorable to the spread of bacteria and fungus. This can result in a nasty odor that is often described as smelling like dirty feet.

Another potential cause of the stench of dirty feet may be a dirty air filter. When your HVAC system's 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 dilemma, 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 prevent the formation of bacteria and fungus.

The Air Conditioning 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 distinct 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 very dangerous and requires immediate attention. If you suspect a gas leak, turn off your air conditioning system, immediately open windows and doors to allow gas to escape the area, make everyone leave the building and call your gas company or emergency services right away.

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 the air conditioning system, it can foster the growth of mold and mildew. This can cause a musty stench that resembles mildew.

Another possible reason for the smell could be a dirty air filter. When the air filter becomes clogged, it can lead to poor air quality and a musty smell that is similar to mildew.

Annual air conditioning maintenance from Kilbourne Heating & AC can help prevent both of these issues, because a good cleaning, inspection and filter change is a great way to keep your system running 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 stinks like urine, it could be due to a variety of factors. One likely cause is a buildup of bacteria or mold in the air conditioning system. This can happen in the event that moisture accumulates in the system and creates a damp environment that can promote bacterial growth. The bacteria can create a foul odor that resembles urine.

Another feasible cause of the scent of urine could be a plugged drain line. The condensation that forms inside the air conditioning unit needs to drain away effectively, but if the drain line becomes clogged with debris, it can cause water to back up and build up 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 system smells like burning plastic, it might be because of an electrical issue with the unit. After some time, the electrical components in the air conditioning system can wear out or malfunction, which can produce a burning smell that resembles plastic.

Another possible cause of the smell could be a foreign object stuck in the the air conditioner. If something foreign gets trapped in the air conditioning system, it can heat up and emit a smell similar to burning plastic.

If you notice something that smells like burning plastic coming from your cooling system, it’s important to contact a professional right away.

My Air Conditioner Smells Like Gas

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

As we said earlier, 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 phone your gas company or emergency services as soon as possible.

My Air Conditioner Smells Like Fish

When your air conditioning equipment smell like fish, you may have a situation where there's a build-up of bacteria or mold in the unit. Moisture creates an environment that fosters the growth of bacteria and mold. This can cause a strong odor that can be described as smelling like fish or, as mentioned earlier, it also can result in a smell like dirty feet.

Another plausible explanation for the smell could be a dead animal or other biological material stuck inside the air conditioning system. This often can happen if an animal such as a mouse or bird is trapped inside the unit and dies.

To solve the issue, it's worthwhile to have a professional inspect and clean your air conditioning system. They can find 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 a home's air conditioning system smells like vinegar. One possible cause is a clogged air filter. One other potential cause of the smell may be a refrigerant leak. If the refrigerant leaks, it can make a chemical odor that resembles vinegar.

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

If you are planning to upgrade, Kilbourne Heating & AC can help select the correct unit to fit your home’s needs. We provide reliable, expert air conditioner installation in Delray Beach.

My Air Conditioner Smells Like Chemicals

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

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

If you suspect a refrigerant leak or an electrical problem, it's important to turn 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 avoid injury or damage to your home.

Weird Smells Coming from Your AC? Call the Pros at Kilbourne Heating & AC

If your air conditioner reeks and you aren’t able to fix it smoothly on your own, reach out to the cooling experts at Kilbourne Heating & AC. We have years of experience working with a wide variety of cooling systems. Our crew has fixed many air conditioning problems over the years—including funky smells. Call us today for quality AC repair in Delray Beach!