The Sniff Test: Why Your Air Conditioner Smells and How to Fix It

When your air conditioner starts spewing unusual 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 may lead to serious damage to your HVAC system or even pose a risk to your health and safety.

Depending on the cause of the odor, the root of the problem could be bacteria or fungus in the system. In other cases, it could also sign something mechanically wrong with the AC. Some smells are a warning of a dangerous situation, such as a natural gas leak.

At Tokay, we are experienced at getting to the root cause of stinky smells. If you smell something peculiar coming from your air conditioner, you can bet that our team of skilled professionals has smelled it, too—and fixed it! We’ve earned our reputation as the premier company for air conditioning repair in Lodi.

What does a specific odor billowing out of your cooling system mean? Here are a few common air conditioner smells and what they might mean:

My Air Conditioner Smells Like Feet

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

Another potential cause of the stench of dirty feet may be a dirty air filter. If an air filter becomes clogged with dirt, dust and other particles, it can lead to poor air quality and a musty smell that it similar to the smell of 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 regularly to promote good air quality and protect against the formation of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioning equipment reeks of rotten eggs, it may 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 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, get everyone out of the building and call your gas company or emergency services at once.

My Air Conditioner Smells Like Mildew

If your AC emits a smell like mildew, it could be due to a collection of moisture inside the unit. When moisture forms inside a cooling system, it can cultivate the growth of mold and mildew. This can cause a musty smell that it similar to mildew.

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

Regular air conditioning maintenance from Tokay can help protect against both of these situations, because a good cleaning, inspection and filter change is a great way to keep your system running at its best!

My Air Conditioner Smells Like Urine

One of the most unpleasant situations is when an air conditioner smells like urine.

If your air conditioning stinks like urine, it could could be caused by multiple factors. One likely cause is a collection of bacteria or mold in the your cooling system. This can happen when moisture accumulates in the system and creates a moist environment that can promote bacterial growth. The bacteria can emit a foul odor that is like urine.

Another potential 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 choked with debris, it can cause water to back up and collect inside the unit. This can create a musty smell that resembles urine.

My Air Conditioner Smells Like Burning Plastic

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

Another possible reason for the smell could be a foreign object that somehow got in the the air conditioner. If something foreign gets caught in the air conditioning system, it can get hot and cause a smell similar to burning plastic.

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

My Air Conditioner 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 smell, often described as smelling like rotten eggs or sulfur. That’s because a smell is added to natural gas so that it is easily detectable.

As we said before, a natural gas leak can be VERY dangerous 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, get everyone out of the building and call your gas company or emergency services straight away.

Why My Air Conditioner 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 is conducive to the growth of bacteria and mold. This can cause a strong odor that is sometimes 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 becomes trapped inside the unit and dies.

To solve the issue, it's important to have a professional check out and clean your air conditioning system. They can identify the source of the smell and take the correct steps to remove any contaminants and keep the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be multiple reasons an air conditioner smells like vinegar. One possible cause might be a dirty air filter. One other likely cause of the smell might be a refrigerant leak. If the refrigerant leaks, it can generate a chemical odor that is similar to vinegar.

To fix the issue, it's essential to have a skilled specialist 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 diagnose 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 planning to upgrade, Tokay can help find the right unit to fit your home’s needs. We provide dependable, expert air conditioner installation in Lodi.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning unit, it could be caused by a refrigerant leak. In a situation where the refrigerant leaks, it can create a chemical scent that people sometimes describe as smelling like chemicals or paint thinner, vinegar or acetone.

One other possible cause of the smell could be an issue with the electrical wiring or hardware inside the air conditioning system. This can result in a burning smell that it similar to chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical problem, it's important to shut off your air conditioning system as soon as possible and contact a professional to inspect and repair the unit. Refrigerant leaks can be harmful and may require immediate attention to protect against injury or damage to your house.

Strange Smell Coming from Your AC? Call the Pros at Tokay

If your air conditioner reeks and you aren’t able to fix it smoothly on your own, reach out to the cooling professionals at Tokay. We have plenty of experience working with a wide variety of AC systems. Our crew has fixed a multitude of air conditioning troubles throughout the years—including funky smells. Call us today for quality AC repair in Lodi!