When your air conditioner starts putting out odd or unappealing aromas, it is important to take notice because it could be a sign of a major problem. Ignoring unpleasant smells coming from your air conditioning may lead to serious 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 indicate something mechanically wrong with the air conditioner. Some smells are even indicative of a hazardous situation, such as a natural gas leak.

At Northglenn Heating & Air Conditioning, we are skilled at diagnosing and fixing these type of problems. If you smell something weird coming from your cooling system, you can bet that our team of qualified professionals has smelled it, too—and fixed it! We’ve earned a reputation as the premier company for air conditioning repair in Northglenn.

What does a particular smell wafting coming from your air conditioning mean? Here are several common 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 inside of it. When moisture accumulates inside the unit, it can establish an environment that is conducive to the development of bacteria and fungus. This can produce a nasty odor that is often described as smelling like feet.

Another likely cause of an odor of stinky feet may be a dirty air filter. If an air filter becomes filled with dirt, dust and other particles, it can result in 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 routinely to promote good air quality and prevent the development of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioning equipment stinks like rotten eggs, it could be because of a natural gas leak in the unit or in the surrounding area. Natural gas has a distinctive 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 extraordinarily 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, make everyone leave the building and call your gas company or emergency services right away.

The Air Conditioning Smells Like Mildew

If your cooling system smells like mildew, it may be due to a buildup 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 resembles mildew.

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

Regular air conditioning maintenance from Northglenn Heating & Air Conditioning can help protect against both of these problems, because a good cleaning, inspection and filter change is a great way to keep your system working at its best!

Your AC Smells Like Urine

One of the most distressing situations is when your AC smells like urine.

If your air conditioning smells like urine, it could be traced back to a number of things. One potential 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 wet environment that is conducive to bacterial growth. The bacteria can create a foul odor that resembles urine.

Another possible cause of the smell could be a blocked drain line. The condensation that forms inside the air conditioning unit needs to drain away correctly, 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.

Your AC Smells Like Burning Plastic

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

Another possible cause of the smell could be a foreign object that somehow got in the unit. If something foreign gets trapped in the air conditioning system, it can get hot and emit a smell like burning plastic.

If you notice something that smells like burning plastic coming from your AC unit, it’s important to call a professional right away.

The Air Conditioning Smells Like Gas

If your air conditioner 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 put into natural gas so that it is easily detectable.

As we said previously, 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 straight away.

Why My Air Conditioner 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 creates an environment that fosters the growth of bacteria and mold. This can cause a foul 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 trapped inside 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 solve the issue, it's worthwhile to have a professional check out and clean your cooling system. They should be able to find 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 numerous reasons your air conditioning system smells like vinegar. One possible cause is a dirty air filter. Another potential cause of the smell could be a refrigerant leak. Sometimes after the refrigerant leaks, it can generate a chemical odor that is similar to vinegar.

To fix the issue, it's important to have a skilled specialist examine and clean your air conditioning.  If the odor persists after the cleaning and replacing 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 looking to upgrade, Northglenn Heating & Air Conditioning can help locate the correct unit to fit your home’s needs. We offer dependable, expert air conditioner installation in Northglenn.

Your AC Smells Like Chemicals

If the smell of chemicals is emitting out of your air conditioning unit, it could be the result of 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.

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

If you believe there is 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 harmful and may require immediate attention to prevent injury or damage to your home.

Weird Smells Coming from the Air Conditioning? Call the Pros at Northglenn Heating & Air Conditioning

If your air conditioner smells nasty and you aren’t able to fix it simply on your own, reach out to the cooling professionals at Northglenn Heating & Air Conditioning. We have plenty of experience working with a wide variety of cooling systems. Our crew has fixed countless air conditioning concerns throughout the years—including funky smells. Call us today for quality AC repair in Northglenn!