When your air conditioner starts spewing odd or unappealing aromas, it is important to take notice because it could be a sign of a big problem. Disregarding unpleasant smells coming from your air conditioning may 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. Other times, it could also sign something mechanically wrong with the air conditioner. Some smells are a sign of a hazardous problem, such as a natural gas leak.

At Heartland Heating & Cooling, we are experienced at getting to the root cause of stinky smells. If you smell something peculiar coming from your AC, chances are our team of skilled pros has smelled it, too—and fixed it! We’ve earned the reputation as the premier company for air conditioning repair in Des Moines.

What does a certain smell wafting out of your AC mean? Here are several frequent air conditioner aromas and what they could mean:

My Air Conditioner Smells Like Feet

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

Another likely cause of an odor of stinky feet might be a dirty air filter. If an air filter becomes filled with dirt, dust and other debris, it can lead to substandard air quality and a musty smell that resembles feet.

To correct this dilemma, 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 change the air filter on a regular basis to ensure good air quality and restrict the growth of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioning unit stinks like rotten eggs, it could 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 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, evacuate the building and call your gas company or emergency services immediately.

My Air Conditioner Smells Like Mildew

If your air conditioner is giving off an odor like mildew, it might be due to a accumulation of moisture inside the unit. When moisture forms inside an air conditioner, it can promote the growth of mold and mildew. This can cause a musty odor that bears a resemblance to mildew.

Another possible explanation for the smell may be a soiled air filter. If the air filter becomes clogged, it can result in poor air quality and a musty smell that resembles mildew.

Routine air conditioning maintenance from Heartland Heating & Cooling can help protect against 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!

My Air Conditioner Smells Like Urine

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

If your air conditioner smells like urine, it could be traced back to a number of things. One possible cause is a buildup of bacteria or mold in the your cooling system. This can happen in the event that moisture accumulates in the system and creates a damp environment that favorable for bacterial growth. The bacteria can create a foul odor that some people describe as smelling like urine.

Another potential 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 properly, but if the drain line becomes clogged with debris, it can cause water to back up and build up inside the unit. This can create a musty smell that resembles urine.

My Air Conditioner Smells Like Burning Plastic

If your air conditioning system smells like burning plastic, a possible cause could be an electrical concern with the unit. After some time, the electrical components in the air conditioning system can wear out or bust, which can make a burning smell that resembles plastic.

Another possible root cause of the smell could be a foreign object lodged in the the air conditioner. If something foreign gets caught in the air conditioning system, it can get hot and emit a smell like burning plastic.

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

My Air Conditioner Smells Like Gas

If your AC smells like gas, it could be due to a natural gas leak in the unit or in the surrounding area. Natural gas has a recognizable smell, often described as smelling of rotten eggs or sulfur. That’s because an odor is added to natural gas so that it is easily detectable.

As we said before, a natural gas leak can be VERY hazardous 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, leave the building and call your gas company or emergency services right away.

Why My Air Conditioner Smells Like Fish

When your air conditioning equipment 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 disgusting odor that is often 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 stuck within the air conditioning system. This often can take place if an animal such as a mouse or bird gets trapped inside the unit and dies.

To fix the issue, it's often necessary 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 prevent the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be multiple reasons your air conditioner smells like vinegar. One possible cause of the smell could be a clogged air filter. A second potential cause of the smell might be a refrigerant leak. If the refrigerant leaks, it can generate a chemical odor that is described as smelling of 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 replacing of 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, the tech can tell you if your air conditioning needs to be replaced.

If you are planning to upgrade, Heartland Heating & Cooling can help select the correct unit to fit your home’s needs. We provide reliable, skilled air conditioner installation in Des Moines.

My Air Conditioner Smells Like Chemicals

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

Another possible cause of the smell could be something wrong with the electrical wiring or elements inside the air conditioning system. This can cause a burning smell that resembles chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical problem, 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 hazardous and may require immediate attention to prevent injury or damage to your house.

Strange Smell Coming from Your AC? Call the Pros at Heartland Heating & Cooling

If your air conditioner smells nasty and you aren’t able to fix it smoothly on your own, contact the cooling professionals at Heartland Heating & Cooling. We have plenty of experience working with a wide variety of cooling systems. Our crew has fixed a multitude of air conditioning concerns over the years—including funky smells. Call us today for quality AC repair in Des Moines!