When your air conditioner starts emitting unusual or unappealing aromas, it is important to take notice because it could be a sign of a significant problem. Dismissing unpleasant smells coming from your cooling system may lead to serious damage to your air conditioning or even pose a risk to your health and safety.

Depending on the smell, the cause may be bacteria or fungus in the system. In other cases, it could also indicate something mechanically wrong with the AC. Some smells are even indicative of a hazardous scenario, like a natural gas leak.

At Central Heating & Plumbing, we are skilled at diagnosing and fixing these type of problems. If you smell something peculiar coming from your AC, chances are our team of talented professionals has smelled it, too—and fixed it! We’ve earned our reputation as the go-to team for air conditioning repair in New Castle.

What does a particular smell coming out of your air conditioning mean? Here are a few frequent air conditioner aromas and what they could mean:

Your AC 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 accumulates inside the unit, it can produce an environment that is favorable to the growth of bacteria and fungus. This can result in a bad odor that is often described as smelling like feet.

Another potential cause of the stench of dirty feet might be a dirty air filter. When the air filter becomes filled with dirt, dust and other debris, it can lead to low air quality and a musty smell that it similar to the smell of feet.

To correct this problem, 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 change the air filter on a regular basis to ensure good air quality and prevent the development of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your smells 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 a situation that 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, evacuate the building and call your gas company or emergency services immediately.

The Air Conditioning Smells Like Mildew

If your AC smells like mildew, it may be due to a buildup of moisture inside the unit. When moisture accumulates inside the air conditioning system, it can promote the growth of mold and mildew. This can cause a musty smell that resembles mildew.

Another possible reason for the smell could be a soiled air filter. When the air filter becomes clogged, it can cause poor air quality and a musty smell that is similar to mildew.

Routine air conditioning maintenance from Central Heating & Plumbing can help prevent both of these issues, because a good cleaning, inspection and filter change is a terrific way to keep your system running at its best!

Your AC Smells Like Urine

One of the most distressing things is when an air conditioner smells like urine.

If your air conditioning equipment stinks like urine, it could be due to a variety of factors. One possible cause is a buildup of bacteria or mold in the your HVAC. 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 some people describe as smelling like urine.

Another potential cause of the smell could be a plugged 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 collect inside the unit. This can produce a musty smell that resembles urine.

The Air Conditioning Smells Like Burning Plastic

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

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

If you smell burning plastic coming from your AC unit, it’s worthwhile 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 the surrounding area. Natural gas has a distinctive smell, often described as smelling of rotten eggs or sulfur. That’s because a smell is incorporated into natural gas to make it easily detectable.

As we said earlier, a natural gas leak can be VERY harmful 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

If your AC smell like fish, it could be due to 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 disgusting odor that can be 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 happen if an animal such as a mouse or bird is trapped inside the unit and dies.

To fix the issue, it's often necessary to have a professional inspect and clean your HVAC system. They can determine the source of the smell and take the correct steps to remove any contaminants and keep the problem from recurring.

The Air Conditioning Smells Like Vinegar

There could be numerous reasons a home's air conditioner smells like vinegar. One possible cause might be a dirty air filter. One other potential cause of the smell might be a refrigerant leak. Sometimes after the refrigerant leaks, it can generate a chemical odor that is similar to vinegar.

To fix the issue, it's important to have a skilled specialist examine and clean your air conditioning.  If the odor continues after the cleaning and replacing of the air filter, it's best to reach back out to a professional to diagnose and repair any persistent issues with your air conditioning. Or, the mechanic can tell you if your air conditioning needs to be replaced.

If you are wanting to upgrade, Central Heating & Plumbing can help find the right unit to fit your home’s needs. We offer dependable, expert air conditioner installation in New Castle.

My Air Conditioner Smells Like Chemicals

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

An additional possible cause of the smell could be something wrong with the electrical wiring or hardware inside the air conditioning system. This can cause 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 down 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 avoid injury or damage to your house.

Strange Smell Coming from Your Cooling? Contact the Experts at Central Heating & Plumbing

If your air conditioner stinks and you aren’t able to fix it smoothly on your own, reach out to the cooling specialists at Central Heating & Plumbing. We have plenty of experience working with a wide variety of cooling systems. Our crew has fixed many air conditioning concerns throughout the years—including weird smells. Call us today for quality AC repair in New Castle!