When your air conditioner starts emitting odd or unappealing aromas, it is necessary to take notice because it could be a sign of a major problem. Dismissing unpleasant smells coming from your cooling system can lead to further damage to your AC or even pose a risk to your health and safety.

Depending on what you're smelling, the culprit may be bacteria or fungus in the system. In other cases, it could also signal something mechanically wrong with the AC. Some smells are even indicative of an unsafe scenario, such as a natural gas leak.

At Patterson & Stirling, we are skilled at diagnosing and fixing these type of problems. If you smell something odd coming from your air conditioner, there's a good chance our team of skilled professionals has smelled it, too—and fixed it! We’ve earned a reputation as the first call for air conditioning repair in Erie.

What does a certain smell coming out of your air conditioning mean? Here are several frequent air conditioner smells and what they might mean:

Your AC Smells Like Feet

If your air conditioner smells like feet, it may be because of a buildup of bacteria or fungus inside of it. When moisture builds inside the unit, it can create an environment that is favorable to the spread of bacteria and fungus. This can result in a bad odor that is often described as smelling like dirty feet.

Another potential explanation for the stench of dirty feet may be a dirty air filter. If an air filter becomes choked with dirt, dust and other contaminants, it can cause substandard air quality and a musty smell that bears a resemblance to feet.

To correct this problem, it's important to have an experienced specialist inspect and clean your air conditioning system, including the evaporator coil, drain pan and condensate drain line. It's also important to change the air filter regularly to promote good air quality and protect against the formation of bacteria and fungus.

The Air Conditioning Smells Like Rotten Eggs

If your air conditioner smells like rotten eggs, it might be caused by 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 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 allow gas to escape the area, get everyone out of the building and call your gas company or emergency services immediately.

My Air Conditioner Smells Like Mildew

If your air conditioner emits a smell like mildew, it might be due to a buildup of moisture inside the unit. When moisture forms inside the air conditioning system, it can promote the growth of mold and mildew. This can cause a musty stench that it similar to mildew.

Another possible explanation for the smell may be a dirty air filter. Once the air filter becomes clogged, it can lead to poor air quality and a musty smell that resembles mildew.

Regular air conditioning maintenance from Patterson & Stirling can help avoid both of these situations, because a good cleaning, inspection and filter change is a very good way to keep your system operating at its best!

Your AC Smells Like Urine

One of the most unpleasant things is when the air coming out of your HVAC system 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 when moisture accumulates in the system and creates a wet environment that is conducive to bacterial growth. The bacteria can produce a foul odor that is like urine.

Another feasible cause of the smell could be a clogged 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.

The Air Conditioning Smells Like Burning Plastic

If your air conditioning unit smells like burning plastic, a possible cause could be an electrical concern with the unit. After a while, the electrical elements in the air conditioning system can wear out or bust, which can make a burning smell that resembles plastic.

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

If you notice something that smells like burning plastic coming from your air conditioner, it’s important to contact a professional right away.

My Air Conditioner Smells Like Gas

If your air conditioner smells like gas, it could be due to a natural gas leak in the unit or in your home. Natural gas has a distinctive aroma, often described as smelling like rotten eggs or sulfur. That’s because this scent is put into natural gas to make sure that it is easily detectable.

As we said previously, a natural gas leak can be VERY hazardous and needs 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 as soon as possible.

My Air Conditioner Smells Like Fish

When 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 causes an environment that is conducive to the growth of bacteria and mold. This can cause a disgusting odor that is often described as smelling like fish or, as mentioned earlier, it also can result in a smell like dirty feet.

Another potential cause of the smell could be a dead animal or other biological material stuck inside the air conditioning system. This often can happen if an animal such as a mouse or bird gets trapped inside the unit and dies.

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

My Air Conditioner Smells Like Vinegar

There could be several reasons your AC smells like vinegar. One possible cause of the smell could be a dirty air filter. Another potential cause of the smell could be a refrigerant leak. If the refrigerant leaks, it can make a chemical odor that is described as smelling of vinegar.

To fix the issue, it's important to have a skilled specialist look at and clean your air conditioning.  If the odor continues after the cleaning and changing of 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, Patterson & Stirling can help locate the right unit to fit your home’s needs. We deliver dependable, professional air conditioner installation in Erie.

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 aroma that people sometimes describe as smelling like chemicals or paint thinner, vinegar or acetone.

Another possible source of the smell could be an issue with the electrical wiring or components inside the air conditioning system. This can produce a burning smell that it similar to chemicals or burning plastic.

If you believe there is a refrigerant leak or an electrical problem, it's important to turn off 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 home.

A Nasty Odor Coming from Your Cooling? Contact the Experts at Patterson & Stirling

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