If Your Air Conditioner Smells, Here's How to Fix It

When your air conditioner starts spewing odd or funky aromas, it is important to take notice because it could be a sign of a significant problem. Disregarding unpleasant smells coming from your cooling system could lead to serious damage to your AC or even pose a risk to your health and safety.

Depending on the cause of the odor, the root of the problem may 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 an unsafe situation, such as a natural gas leak.

At Forster Heating, we have a nose for these sorts of things. If you smell something weird coming from your AC, chances are our team of qualified professionals has smelled it, too—and fixed it! We’ve earned the reputation as the go-to team for air conditioning repair in Auburn.

What does a particular smell wafting from your AC mean? Here are some frequent air conditioner smells and what they may mean:

Your AC Smells Like Feet

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

Another potential reason for an odor of stinky feet could be a dirty air filter. When the air filter becomes clogged with dirt, dust and other debris, it can result in low air quality and a musty smell that resembles feet.

To solve 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 on a regular basis to promote 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 might be caused by 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, which is because of a substance added to it to make it easily detectable.

A natural gas leak is a situation that 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 ventilate the area, get everyone out of the building and call your gas company or emergency services right away.

Your AC Smells Like Mildew

If your air conditioner is giving off an odor like mildew, it might be due to a accumulation of moisture inside the unit. When moisture forms inside an air conditioner, it can foster the growth of mold and mildew. This can cause a musty odor that it similar to mildew.

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

Annual air conditioning maintenance from Forster Heating can help prevent both of these situations, because a good cleaning, inspection and filter change is a very good way to keep your system running at its best!

My Air Conditioner Smells Like Urine

One of the most unpleasant scenarios is when your AC smells like urine.

If your air conditioning equipment reeks of urine, it could be due to a variety of factors. 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 moist 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 stopped up by debris, it can cause water to back up and accumulate inside the unit. This can generate a musty smell that is sometimes described as smelling of urine.

My Air Conditioner Smells Like Burning Plastic

If your air conditioner smells like burning plastic, this could indicate an electrical issue with the unit. After some time, the electrical elements in the air conditioning system can wear out or malfunction, which can create a burning smell that resembles plastic.

Another possible cause of the smell could be a foreign object that somehow got in the HVAC system. If something foreign gets caught in the air conditioning system, it can heat up and emit a smell similar to burning plastic.

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

Your AC Smells Like Gas

If your air conditioner 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 distinctive smell, often described as smelling like rotten eggs or sulfur. That’s because an odor is incorporated into natural gas so that it is easily detectable.

As stated before, a natural gas leak can be VERY dangerous and calls for immediate attention. When 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 as soon as possible.

The Air Conditioning Smells Like Fish

Should your air conditioning equipment smell like fish, you may have a situation where there's a build-up of bacteria or mold in the unit. Moisture creates an environment that promotes the growth of bacteria and mold. This can cause a foul 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 caught inside the air conditioning system. This often is possible if an animal such as a mouse or bird is trapped inside the unit and dies.

To fix the issue, it's important to have a professional examine and clean your cooling system. They should be able to determine 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 multiple reasons an AC smells like vinegar. One possible cause of the smell could be a dirty air filter. Another potential cause of the smell may be a refrigerant leak. Sometimes after the refrigerant leaks, it can make a chemical odor that is similar to 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 changing of the air filter, it's best to reach back out to a professional to find and repair any persistent issues with your air conditioning. Or, the tech can tell you if your air conditioning needs to be replaced.

If you are looking to upgrade, Forster Heating can help find the right unit to fit your home’s needs. We offer trustworthy, professional air conditioner installation in Auburn.

Your AC Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning unit, it could be due to a refrigerant leak. If the refrigerant leaks, it can create a chemical odor that some people describe as smelling like chemicals or paint thinner, vinegar or acetone.

One other possible cause of the smell could be something wrong with the electrical wiring or parts inside the air conditioning system. This can produce a burning smell that resembles chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical concern, 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 dangerous and may require immediate attention to avoid injury or damage to your home.

Strange Smell Coming from the Air Conditioning? Call the Pros at Forster Heating

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