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

When your air conditioner starts emitting odd or gross odors, it is a good idea to take notice because it could be a sign of a significant problem. Disregarding unpleasant smells coming from your air conditioning can lead to further damage to your air conditioning or even pose a risk to your health and safety.

Depending on what you're smelling, the root of the problem might be bacteria or fungus in the system. Other times, it could also signal something mechanically wrong with the AC. Some smells are even indicative of an unsafe problem, such as a natural gas leak.

At Precision Mechanical, we are skilled at diagnosing and fixing these type of problems. If you smell something weird coming from your AC, you can bet that our team of qualified pros has smelled it, too—and fixed it! We’ve earned the reputation as the go-to team for air conditioning repair in Rapid City.

What does a specific odor wafting out of your AC mean? Here are a few common air conditioner odors and what they might mean:

Your AC Smells Like Feet

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

Another likely explanation for the smell could be a dirty air filter. When your HVAC system's air filter becomes clogged with dirt, dust and other contaminants, it can cause substandard air quality and a musty smell that resembles 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 replace the air filter routinely to provide good air quality and protect against the development of bacteria and fungus.

Your AC Smells Like Rotten Eggs

If your 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 a situation that is extremely 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, evacuate the building and call your gas company or emergency services right away.

My Air Conditioner Smells Like Mildew

If your AC is giving off an odor like mildew, it could 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 bears a resemblance to mildew.

Another possible explanation for the smell may be a soiled air filter. Once the air filter becomes clogged, it can result in poor air quality and a musty smell that has a resemblance to mildew.

Annual air conditioning maintenance from Precision Mechanical can help avoid both of these situations, because a good cleaning, inspection and filter change is a great way to keep your system operating at its best!

My Air Conditioner Smells Like Urine

One of the most unpleasant scenarios is when the air coming out of your HVAC system smells like urine.

If your air conditioner stinks like urine, it could be due to a variety of factors. One likely cause is a buildup of bacteria or mold in the your cooling system. This can happen in the event that moisture accumulates in the system and creates a wet environment that favorable for bacterial growth. The bacteria can emit a foul odor that some people describe as smelling like urine.

Another potential 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 accumulate inside the unit. This can generate a musty smell that resembles urine.

My Air Conditioner Smells Like Burning Plastic

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

Another possible reason for the smell could be a foreign object lodged in the the air conditioner. If something foreign gets stuck in the air conditioning system, it can become hot and result in a smell that reminds people of burning plastic.

If you think 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 your home. Natural gas has a distinctive aroma, often described as smelling similar to rotten eggs or sulfur. That’s because this scent is incorporated into natural gas so that it is easily detectable.

As mentioned before, a natural gas leak can be VERY harmful and requires 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 right away.

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 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 trapped inside the air conditioning system. This often can happen if an animal such as a mouse or bird becomes trapped inside the unit and dies.

To correct the issue, it's often necessary to have a professional examine and clean your cooling system. They can find the source of the smell and take the correct steps to remove any contaminants and stop the problem from recurring.

My Air Conditioner Smells Like Vinegar

There could be several reasons an air conditioner smells like vinegar. One possible cause might be a clogged air filter. One other possible cause of the smell might be a refrigerant leak. When the refrigerant leaks, it can make a chemical odor that is similar to vinegar.

To fix the issue, it's important to have a skilled tech inspect and clean your air conditioning.  If the odor persists after the cleaning and exchanging 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 mechanic can tell you if your air conditioning ought to be replaced.

If you are wanting to upgrade, Precision Mechanical can help find the correct unit to fit your home’s needs. We deliver trustworthy, skilled air conditioner installation in Rapid City.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming from your air conditioning unit, it could be due to a refrigerant leak. When the refrigerant leaks, it can create a chemical scent that is often described 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 parts 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 problem, it's important to shut off your air conditioning system immediately and contact a professional to inspect and repair the unit. Refrigerant leaks can be hazardous and may require immediate attention to avoid injury or damage to your house.

Strange Smell Coming from Your Cooling? Contact the Experts at Precision Mechanical

If your air conditioner smells nasty and you aren’t able to fix it easily on your own, call the cooling specialists at Precision Mechanical. We have plenty of experience working with a wide variety of air conditioning systems. Our crew has fixed countless air conditioning concerns over the years—including funky smells. Call us today for quality AC repair in Rapid City!