When your air conditioner starts putting out weird 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 cooling system may lead to additional damage to your HVAC system or even pose a risk to your health and safety.

Depending on the smell, the cause might be bacteria or fungus in the system. In other cases, it could also sign something mechanically wrong with the air conditioning system. Some smells are a sign of a hazardous problem, such as a natural gas leak.

At Kohles & Bach Heating & Cooling, we have a nose for these sorts of things. If you smell something odd coming from your AC, chances are our team of skilled professionals has smelled it, too—and fixed it! We’ve earned the reputation as the go-to team for air conditioning repair in Des Moines.

What does a specific odor wafting out of your cooling system mean? Here are some typical air conditioner odors and what they could mean:

The Air Conditioning Smells Like Feet

If your air conditioner smells like feet, it might be because of a buildup of bacteria or fungus in the unit. When moisture builds inside the unit, it can produce an environment that is beneficial to the spread of bacteria and fungus. This can produce a bad odor that is often described as smelling like stinky feet.

Another possible cause of an odor of stinky feet could be a dirty air filter. When your HVAC system's air filter becomes choked with dirt, dust and other debris, it can result in poor air quality and a musty smell that bears a resemblance to feet.

To fix this problem, 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 exchange the air filter regularly to provide good air quality and protect against the growth of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioner smells like rotten eggs, it may 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, that is 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 ventilate the area, make everyone leave the building and call your gas company or emergency services immediately.

Your AC Smells Like Mildew

If your AC emits a smell like mildew, it may be due to a collection of moisture inside the unit. When moisture collects inside a cooling system, it can cultivate the growth of mold and mildew. This can cause a musty odor that it similar to mildew.

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

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

The Air Conditioning Smells Like Urine

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

If your air conditioning smells like urine, it could be due to a variety of factors. One potential cause is a accumulation of bacteria or mold in the air conditioning system. This can happen in the event that moisture accumulates in the system and creates a moist environment that favorable for bacterial growth. The bacteria can create a foul odor that resembles urine.

Another possible 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 effectively, but if the drain line becomes choked with debris, it can cause water to back up and build up inside the unit. This can produce a musty smell that can stink like urine.

The Air Conditioning Smells Like Burning Plastic

If your air conditioning unit smells like burning plastic, this could indicate an electrical issue with the unit. Over time, the electrical elements 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 that somehow got in the HVAC system. If something foreign gets caught in the air conditioning system, it can heat up and result in a smell like burning plastic.

If you notice something that smells like burning plastic coming from your air conditioner, it’s essential to call a professional right away.

Your AC 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 distinct smell, often described as smelling like rotten eggs or sulfur. That’s because an odor is incorporated into natural gas to make sure that it is easily detectable.

As we said earlier, a natural gas leak can be VERY dangerous and requires immediate attention. Should 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 phone your gas company or emergency services straight away.

Your AC Smells Like Fish

When your AC smell like fish, it could be due to a build-up of bacteria or mold in the unit. Moisture produces an environment that fosters the growth of bacteria and mold. This can cause a foul odor that is often 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 stuck inside 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 should be able to identify the source of the smell and take the appropriate steps to remove any contaminants and stop the problem from recurring.

The Air Conditioning Smells Like Vinegar

There could be multiple reasons a home's air conditioner smells like vinegar. One possible cause of the smell could be a clogged air filter. One other possible cause of the smell could 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 beneficial to have a skilled mechanic examine and clean your air conditioning.  If the odor continues after the cleaning and exchanging the air filter, it's best to reach back out to a professional to identify and repair any persistent issues with your air conditioning. Or, the tech can tell you if your air conditioning ought to be replaced.

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

The Air Conditioning Smells Like Chemicals

If the smell of chemicals is coming from your air conditioning equipment, it could be due to a refrigerant leak. When 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 cause of the smell could be a problem with the electrical wiring or components inside the air conditioning system. This can result in 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 shut down your air conditioning system right away 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 residence.

Strange Smell Coming from the Air Conditioning? Call the Pros at Kohles & Bach Heating & Cooling

If your air conditioner reeks and you aren’t able to fix it easily on your own, reach out to the cooling professionals at Kohles & Bach Heating & Cooling. We have lots of experience working with a wide variety of cooling systems. Our crew has fixed countless air conditioning troubles through the years—including weird smells. Call us today for quality AC repair in Des Moines!