When your air conditioner starts emitting strange or unappealing 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 cooling system can lead to additional damage to your AC or even pose a risk to your health and safety.

Depending on what you're smelling, the cause may be bacteria or fungus in the system. In other cases, it could also signal something mechanically wrong with the AC. Some smells are a warning of a hazardous situation, such as a natural gas leak.

At Kohles & Bach Heating & Cooling, we are skilled at diagnosing and fixing these type of problems. If you smell something odd coming from your cooling system, there's a good chance our team of talented specialists has smelled it, too—and fixed it! We’ve earned our reputation as the first call for air conditioning repair in Des Moines.

What does a certain smell billowing coming from your cooling system mean? Here are a few common air conditioner smells and what they may mean:

Your AC Smells Like Feet

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

Another likely reason for the smell could be a dirty air filter. When your HVAC system's air filter becomes choked with dirt, dust and other contaminants, it can cause poor air quality and a musty smell that resembles feet.

To fix this problem, 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 exchange the air filter on a regular basis to promote good air quality and restrict the formation of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your stinks like rotten eggs, it might be because 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 can be 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, get everyone out of the building and call your gas company or emergency services immediately.

Your AC Smells Like Mildew

If your cooling system is giving off an odor like mildew, it may be due to a buildup of moisture inside the unit. When moisture accumulates inside the air conditioning system, it can cultivate the growth of mold and mildew. This can cause a musty odor that bears a resemblance to mildew.

Another possible cause of the smell might be a soiled air filter. When the air filter becomes clogged, it can result in poor air quality and a musty smell that has a resemblance to mildew.

Annual air conditioning maintenance from Kohles & Bach Heating & Cooling can help avoid both of these problems, because a good cleaning, inspection and filter change is a great way to keep your system working at its best!

The Air Conditioning Smells Like Urine

One of the most unpleasant scenarios is when an air conditioner smells like urine.

If your air conditioning equipment stinks like urine, it could be traced back to a number of things. One possible cause is a accumulation of bacteria or mold in the air conditioning system. This can happen if 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 potential cause of the smell could be a blocked drain line. The condensation that forms inside the air conditioning unit needs to drain away properly, but if the drain line becomes stopped up by debris, it can cause water to back up and build up inside the unit. This can produce a musty smell that resembles urine.

My Air Conditioner Smells Like Burning Plastic

If your air conditioning system smells like burning plastic, this could indicate an electrical problem with the unit. After some time, the electrical elements in the air conditioning system can wear out or malfunction, which can make a burning smell that resembles plastic.

Another possible reason for the smell could be a foreign object lodged in the the air conditioner. 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 notice something that smells like burning plastic coming from your AC unit, it’s essential to contact a professional right away.

My Air Conditioner Smells Like Gas

If your air conditioner smells like gas, it could be due to a natural gas leak in the unit or in your home. Natural gas has a distinctive smell, often described as smelling similar to rotten eggs or sulfur. That’s because an odor is incorporated into natural gas to make it easily detectable.

As we said before, a natural gas leak can be VERY dangerous 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, evacuate the building and call your gas company or emergency services as soon as possible.

My Air Conditioner Smells Like Fish

When your AC 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 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 within 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 important to have a professional inspect and clean your air conditioning system. They should be able to identify the source of the smell and take the proper steps to remove any contaminants and stop the problem from recurring.

My Air Conditioner Smells Like Vinegar

There could be numerous reasons your air conditioning system smells like vinegar. One possible cause is a plugged air filter. One other possible cause of the smell might be a refrigerant leak. When the refrigerant leaks, it can generate a chemical odor that resembles vinegar.

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

If you are wanting to upgrade, Kohles & Bach Heating & Cooling can help find the right unit to fit your home’s needs. We offer trustworthy, expert air conditioner installation in Des Moines.

The Air Conditioning Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning equipment, it could be caused by a refrigerant leak. In a situation where the refrigerant leaks, it can create a chemical aroma that people sometimes describe as smelling like chemicals or paint thinner, vinegar or acetone.

Another possible reason for the smell could be a problem with the electrical wiring or elements inside the air conditioning system. This can cause a burning smell that is like chemicals or burning plastic.

If you think your system has a refrigerant leak or an electrical concern, it's important to shut off your air conditioning system right away and contact a professional to inspect and repair the unit. Refrigerant leaks can be harmful and may require immediate attention to protect against injury or damage to your home.

Strange Smell Coming from Your AC? Contact the Experts at Kohles & Bach Heating & Cooling

If your air conditioner reeks and you aren’t able to fix it simply on your own, call the cooling experts at Kohles & Bach Heating & Cooling. We have lots of experience working with a wide variety of air conditioning systems. Our crew has fixed a multitude of air conditioning concerns throughout the years—including strange smells. Call us today for quality AC repair in Des Moines!