When your air conditioner starts emitting unusual or unappealing smells, it is necessary to take notice because it could be a sign of a major problem. Ignoring unpleasant smells coming from your cooling system may lead to additional damage to your air conditioning or even pose a risk to your health and safety.

Depending on the cause of the odor, the cause might be bacteria or fungus in the system. In other cases, it could also indicate something mechanically wrong with the air conditioner. Some smells are a warning of a dangerous scenario, like a natural gas leak.

At Olde Towne Heating & Air, we have a nose for these sorts of things. If you smell something odd coming from your AC, you can bet that our team of skilled professionals has smelled it, too—and fixed it! We’ve earned our reputation as the first call for air conditioning repair in Mount Pleasant.

What does a certain smell coming out of your air conditioning mean? Here are a few typical air conditioner odors and what they might 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 unit. When moisture builds inside the unit, it can create an environment that is favorable to the growth of bacteria and fungus. This can cause a foul odor that is often described as smelling like dirty feet.

Another likely reason for an odor of stinky feet could be a dirty air filter. If an air filter becomes choked with dirt, dust and other particles, it can result in low air quality and a musty smell that resembles feet.

To correct this issue, 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 replace the air filter on a regular basis to provide good air quality and prevent the development 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 distinct 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 extraordinarily 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, evacuate the building and call your gas company or emergency services immediately.

My Air Conditioner Smells Like Mildew

If your AC smells like mildew, it might be due to a buildup of moisture inside the unit. When moisture collects inside a cooling system, it can foster the growth of mold and mildew. This can cause a musty odor that it similar to mildew.

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

Regular air conditioning maintenance from Olde Towne Heating & Air can help avoid both of these problems, because a good cleaning, inspection and filter change is a terrific way to keep your system operating at its best!

Your AC Smells Like Urine

One of the most undesirable scenarios 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 likely cause is a accumulation of bacteria or mold in the your HVAC. This can happen if moisture accumulates in the system and creates a moist environment that is conducive to bacterial growth. The bacteria can create a foul odor that some people describe as smelling like urine.

Another possible 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 effectively, but if the drain line becomes stopped up by debris, it can cause water to back up and build up inside the unit. This can produce a musty smell that is sometimes described as smelling of 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 a while, the electrical components in the air conditioning system can wear out or malfunction, which can make a burning smell that resembles plastic.

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

My Air Conditioner Smells Like Gas

If your air conditioner smells like gas, there could be a natural gas leak in the unit or in another part of your home. Natural gas has a recognizable odor, often described as smelling like rotten eggs or sulfur. That’s because a smell is put into natural gas so that it is easily detectable.

As mentioned previously, a natural gas leak can be VERY harmful 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 phone your gas company or emergency services right away.

Your AC Smells Like Fish

When your AC smell like fish, this could be a sign of a build-up of bacteria or mold in the unit. Moisture creates an environment that is conducive to 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 create a smell like dirty feet.

Another plausible explanation for 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 gets trapped inside the unit and dies.

To fix the issue, it's often necessary to have a professional check out and clean your HVAC system. They should be able to find the source of the smell and take the proper steps to remove any contaminants and prevent the problem from recurring.

My Air Conditioner Smells Like Vinegar

There could be numerous reasons an AC smells like vinegar. One possible cause is a clogged air filter. A second potential cause of the smell could be a refrigerant leak. If the refrigerant leaks, it can generate a chemical odor that resembles vinegar.

To fix the issue, it's beneficial to have a skilled tech inspect 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 hidden issues with your air conditioning. Or, the mechanic can tell you if your air conditioning should be replaced.

If you are wanting to upgrade, Olde Towne Heating & Air can help locate the correct unit to fit your home’s needs. We provide reliable, professional air conditioner installation in Mount Pleasant.

Your AC Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioner, it could be due to a refrigerant leak. When 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 result in a burning smell that is like chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical concern, 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.

Weird Smells Coming from Your AC? Call the Pros at Olde Towne Heating & Air

If your air conditioner reeks and you aren’t able to fix it simply on your own, contact the cooling specialists at Olde Towne Heating & Air. We have years of experience working with a wide variety of cooling systems. Our crew has fixed countless air conditioning problems through the years—including funky smells. Call us today for quality AC repair in Mount Pleasant!