When your air conditioner starts emitting weird or funky aromas, it is a good idea to take notice because it could be a sign of a major problem. Ignoring unpleasant smells coming from your air conditioner may lead to serious damage to your HVAC system or even pose a risk to your health and safety.

Depending on what you're smelling, the culprit might be bacteria or fungus in the system. On the other hand, it could also indicate something mechanically wrong with the AC. Some smells are a warning of a hazardous scenario, including a natural gas leak.

At Farnell Mechanical, Inc., we have a nose for these sorts of things. If you smell something odd coming from your cooling system, you can bet that our team of qualified pros has smelled it, too—and fixed it! We’ve earned the reputation as the first call for air conditioning repair in Auburn and Opelika.

What does a specific odor billowing coming from your air conditioning mean? Here are several common air conditioner aromas and what they could mean:

My Air Conditioner Smells Like Feet

If your air conditioner smells like feet, it may be due to a buildup of bacteria or fungus inside of it. When moisture builds inside the unit, it can create an environment that is beneficial to the development of bacteria and fungus. This can cause a bad odor that is often described as smelling like feet.

Another potential explanation for 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 particles, it can lead to substandard air quality and a musty smell that bears a resemblance to feet.

To fix this unpleasant situation, it's important to have a quality service tech 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 formation of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioner reeks of rotten eggs, it could be due to 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 because of a substance 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 air out the area, make everyone leave the building and call your gas company or emergency services at once.

The Air Conditioning Smells Like Mildew

If your AC smells like mildew, it might be due to a buildup of moisture inside the unit. When moisture accumulates inside the air conditioning system, 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 could be a soiled air filter. Once the air filter becomes clogged, it can lead to poor air quality and a musty smell that is similar to mildew.

Routine air conditioning maintenance from Farnell Mechanical, Inc. can help protect against both of these situations, because a good cleaning, inspection and filter change is a very good way to keep your system working at its best!

Your AC Smells Like Urine

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

If your air conditioner reeks of urine, it could be traced back to a number of things. One possible cause is a accumulation of bacteria or mold in the your HVAC. This can happen when moisture accumulates in the system and creates a damp environment that is conducive to bacterial growth. The bacteria can produce a foul odor that it similar to urine.

Another feasible cause of the stink 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 generate a musty smell that resembles urine.

The Air Conditioning Smells Like Burning Plastic

If your air conditioning system smells like burning plastic, it might be because of an electrical problem with the unit. After a while, the electrical components in the air conditioning system can wear out or bust, which can make a burning smell that resembles plastic.

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

If you think you smell burning plastic coming from your air conditioner, it’s worthwhile to call a professional right away.

Your AC Smells Like Gas

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

As stated previously, a natural gas leak can be VERY hazardous 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 call your gas company or emergency services straight away.

The Air Conditioning Smells Like Fish

Should your air conditioner 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 disgusting odor that is often described as smelling like fish or, as mentioned earlier, it also can create 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 is possible if an animal such as a mouse or bird becomes trapped inside the unit and dies.

To solve the issue, it's often necessary to have a professional inspect and clean your air conditioning system. They will be able to identify the source of the smell and take the proper steps to remove any contaminants and prevent the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be several reasons your air conditioner smells like vinegar. One possible cause is a clogged air filter. Another potential cause of the smell could be a refrigerant leak. If the refrigerant leaks, it can create a chemical odor that is described as smelling of vinegar.

To fix the issue, it's essential to have a skilled mechanic look at 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 identify and repair any underlying issues with your air conditioning. Or, the tech can tell you if your air conditioning should be replaced.

If you are looking to upgrade, Farnell Mechanical, Inc. can help select the right unit to fit your home’s needs. We deliver trustworthy, expert air conditioner installation in Auburn and Opelika.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is emitting out of your air conditioning unit, it could be caused by a refrigerant leak. When the refrigerant leaks, it can create a chemical scent 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 hardware inside the air conditioning system. This can result in a burning smell that resembles chemicals or burning plastic.

If you believe there is a refrigerant leak or an electrical issue, 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 dangerous and may require immediate attention to protect against injury or damage to your residence.

A Nasty Odor Coming from Your Cooling? Call the Pros at Farnell Mechanical, Inc.

If your air conditioner stinks and you aren’t able to fix it simply on your own, reach out to the cooling experts at Farnell Mechanical, Inc.. We have years of experience working with a wide variety of cooling systems. Our crew has fixed many air conditioning problems through the years—including weird smells. Call us today for quality AC repair in Auburn and Opelika!