When your air conditioner starts putting out strange or gross odors, it is necessary to take notice because it could be a sign of a significant problem. Ignoring unpleasant smells coming from your cooling system can lead to serious damage to your HVAC system or even pose a risk to your health and safety.

Depending on the smell, the cause might be bacteria or fungus in the system. In other cases, it could also signal something mechanically wrong with the air conditioner. Some smells are a sign of a dangerous situation, such as a natural gas leak.

At Service Max Heating & Air Conditioning, we have a nose for these sorts of things. If you smell something peculiar coming from your cooling system, there's a good chance our team of talented pros has smelled it, too—and fixed it! We’ve earned the reputation as the first call for air conditioning repair in Arlington.

What does a certain smell coming coming from your air conditioning mean? Here are some frequent air conditioner odors and what they may mean:

The Air Conditioning Smells Like Feet

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

Another likely explanation for the smell may be a dirty air filter. When the air filter becomes filled with dirt, dust and other particles, it can cause low air quality and a musty smell that it similar to the smell of feet.

To fix 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 exchange the air filter regularly to promote good air quality and protect against the growth of bacteria and fungus.

Your AC Smells Like Rotten Eggs

If your stinks like rotten eggs, it might be the result of 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, evacuate the building and call your gas company or emergency services immediately.

The Air Conditioning Smells Like Mildew

If your air conditioner emits a smell like mildew, it may be due to a accumulation of moisture inside the unit. When moisture forms inside the air conditioning system, it can foster the growth of mold and mildew. This can cause a musty smell that bears a resemblance to mildew.

Another possible reason for the smell may be a soiled air filter. If 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 Service Max Heating & Air Conditioning can help avoid both of these problems, 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 distressing situations is when the air coming out of your HVAC system smells like urine.

If your air conditioning equipment reeks of urine, it could be due to a variety of factors. One possible cause is a accumulation of bacteria or mold in the your cooling system. This can happen in the event that moisture accumulates in the system and creates a damp environment that favorable for bacterial growth. The bacteria can emit a foul odor that resembles urine.

Another feasible cause of the scent of urine could be a blocked drain line. The condensation that forms inside the air conditioning unit needs to drain away effectively, but if the drain line becomes filled with debris, it can cause water to back up and collect inside the unit. This can generate a musty smell that can stink like urine.

My Air Conditioner Smells Like Burning Plastic

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

Another possible cause of the smell could be a foreign object lodged in the HVAC system. If something foreign gets stuck in the air conditioning system, it can become hot and emit a smell like burning plastic.

If you smell burning plastic coming from your cooling system, it’s important to call a professional right away.

Your AC Smells Like Gas

If your air conditioning smells like gas, it could be because of a natural gas leak in the unit or in your home. Natural gas has a distinct odor, 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 mentioned previously, a natural gas leak can be VERY hazardous and needs immediate attention. If 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 as soon as possible.

Your AC Smells Like Fish

When 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 sometimes described as smelling like fish or, as mentioned earlier, it also can create a smell like dirty feet.

Another possible cause of the smell could be a dead animal or other biological material stuck 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 correct the issue, it's important to have a professional check out and clean your HVAC system. They can find the source of the smell and take the correct steps to remove any contaminants and keep the problem from recurring.

Your AC Smells Like Vinegar

There could be numerous reasons your air conditioner smells like vinegar. One possible cause is a dirty air filter. A second likely cause of the smell may be a refrigerant leak. Sometimes after the refrigerant leaks, it can generate a chemical odor that is described as smelling of vinegar.

To fix the issue, it's important to have a skilled specialist inspect 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 diagnose and repair any hidden issues with your air conditioning. Or, they can tell you if your air conditioning should be replaced.

If you are planning to upgrade, Service Max Heating & Air Conditioning can help select the right unit to fit your home’s needs. We offer dependable, professional air conditioner installation in Arlington.

Your AC Smells Like Chemicals

If the smell of chemicals is emitting out of your air conditioning unit, it could be the result of a refrigerant leak. When 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 problems with the electrical wiring or components inside the air conditioning system. This can cause a burning smell that resembles chemicals or burning plastic.

If you think your system has 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 hazardous and may require immediate attention to prevent injury or damage to your residence.

A Nasty Odor Coming from Your Cooling? Call the Pros at Service Max Heating & Air Conditioning

If your air conditioner stinks and you aren’t able to fix it simply on your own, call the cooling experts at Service Max Heating & Air Conditioning. We have plenty of experience working with a wide variety of cooling systems. Our crew has fixed a multitude of air conditioning concerns through the years—including funky smells. Call us today for quality AC repair in Arlington!