When your air conditioner starts spewing weird or unappealing aromas, it is necessary to take notice because it could be a sign of a big problem. Dismissing unpleasant smells coming from your cooling system can lead to additional damage to your HVAC system or even pose a risk to your health and safety.

Depending on the cause of the odor, the cause may be bacteria or fungus in the system. Other times, it could also sign something mechanically wrong with the air conditioning system. Some smells are a warning of a dangerous problem, like a natural gas leak.

At Integrity AC & Heating LLC, we are experienced at getting to the root cause of stinky smells. If you smell something odd coming from your air conditioner, you can bet that our team of qualified specialists has smelled it, too—and fixed it! We’ve earned our reputation as the go-to team for air conditioning repair in Phoenix.

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

The Air Conditioning Smells Like Feet

If your air conditioner smells like feet, it may 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 favorable to the growth of bacteria and fungus. This can cause a nasty odor that is often described as smelling like feet.

Another likely explanation for the smell might be a dirty air filter. When the air filter becomes clogged with dirt, dust and other contaminants, it can result in substandard air quality and a musty smell that it similar to the smell of feet.

To solve this unpleasant situation, 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 routinely to provide good air quality and protect against the growth of bacteria and fungus.

The Air Conditioning Smells Like Rotten Eggs

If your stinks like rotten eggs, it may be due to a natural gas leak in the unit or in the surrounding area. Natural gas has a unique odor, often described as smelling like rotten eggs or sulfur, that is 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, evacuate the building and call your gas company or emergency services immediately.

Your AC Smells Like Mildew

If your cooling system smells like mildew, it might be due to a buildup of moisture inside the unit. When moisture forms inside the air conditioning system, it can promote the growth of mold and mildew. This can cause a musty stench that it similar to mildew.

Another possible cause of the smell could be a dirty air filter. Once the air filter becomes clogged, it can cause poor air quality and a musty smell that is similar to mildew.

Regular air conditioning maintenance from Integrity AC & Heating LLC can help prevent both of these situations, because a good cleaning, inspection and filter change is a terrific way to keep your system working at its best!

The Air Conditioning Smells Like Urine

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

If your air conditioning reeks of urine, it could could be caused by multiple factors. One possible cause is a collection of bacteria or mold in the your cooling system. This can happen if moisture accumulates in the system and creates a wet environment that can promote bacterial growth. The bacteria can create a foul odor that resembles urine.

Another potential cause of the scent of urine 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 filled with debris, it can cause water to back up and accumulate inside the unit. This can create a musty smell that can stink like urine.

Your AC Smells Like Burning Plastic

If your air conditioning unit smells like burning plastic, it might be because of an electrical problem with the unit. After some time, the electrical elements in the air conditioning system can wear out or break, which can create a burning smell that resembles plastic.

Another possible reason for the smell could be a foreign object lodged in the HVAC system. If something foreign gets stuck in the air conditioning system, it can become hot and cause a smell like burning plastic.

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

Your AC Smells Like Gas

If your air conditioning smells like gas, it could be because of a natural gas leak in the unit or in another part of your home. Natural gas has a distinct smell, often described as smelling similar to rotten eggs or sulfur. That’s because a smell is added to natural gas to make sure that it is easily detectable.

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

The Air Conditioning Smells Like Fish

Should your air conditioning equipment smell like fish, this could be a sign of a build-up of bacteria or mold in the unit. Moisture causes an environment that fosters the growth of bacteria and mold. This can cause a strong odor that is often 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 trapped within 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 fix the issue, it's often necessary to have a professional examine and clean your HVAC system. They can find the source of the smell and take the proper steps to remove any contaminants and stop the problem from recurring.

Your AC Smells Like Vinegar

There could be multiple reasons your air conditioner smells like vinegar. One possible cause of the smell could be a plugged air filter. A second likely cause of the smell could be a refrigerant leak. Sometimes after the refrigerant leaks, it can make a chemical odor that is described as smelling of vinegar.

To fix the issue, it's important to have a skilled specialist look at 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, Integrity AC & Heating LLC can help locate the ideal unit to fit your home’s needs. We deliver reliable, expert air conditioner installation in Phoenix.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming from your air conditioner, it could be due to a refrigerant leak. If 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 a problem with the electrical wiring or parts inside the air conditioning system. This can result in a burning smell that is like chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical issue, 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 prevent injury or damage to your home.

A Nasty Odor Coming from Your Cooling? Call the Pros at Integrity AC & Heating LLC

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