When your air conditioner starts putting out strange or unappealing smells, it is a good idea to take notice because it could be a sign of a significant problem. Dismissing unpleasant smells coming from your air conditioner could lead to additional damage to your air conditioning or even pose a risk to your health and safety.

Depending on what you're smelling, the cause could be bacteria or fungus in the system. Other times, it could also signal something mechanically wrong with the air conditioner. Some smells are a sign of a dangerous problem, such as a natural gas leak.

At Indoor Comfort Systems HVAC, we have a nose for these sorts of things. If you smell something peculiar 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 the reputation as the go-to team for air conditioning repair in Croydon.

What does a specific odor coming out of your air conditioning mean? Here are several frequent air conditioner aromas and what they could mean:

The Air Conditioning 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 builds inside the unit, it can produce an environment that is beneficial to the development of bacteria and fungus. This can produce a nasty odor that is often described as smelling like dirty feet.

Another potential reason for the stench of dirty feet might be a dirty air filter. If an air filter becomes clogged with dirt, dust and other debris, it can result in substandard air quality and a musty smell that it similar to the smell of feet.

To fix 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 exchange the air filter on a regular basis to promote good air quality and prevent the growth of bacteria and fungus.

Your AC Smells Like Rotten Eggs

If your air conditioning unit smells like rotten eggs, it could be due to 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 added to it to make it easily detectable.

A natural gas leak 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, make everyone leave the building and call your gas company or emergency services at once.

Your AC Smells Like Mildew

If your AC is giving off an odor like mildew, it might be due to a accumulation of moisture inside the unit. When moisture forms inside the air conditioning system, it can cultivate the growth of mold and mildew. This can cause a musty odor that bears a resemblance to mildew.

Another possible cause of the smell may be a dirty air filter. When the air filter becomes clogged, it can result in poor air quality and a musty smell that is similar to mildew.

Regular air conditioning maintenance from Indoor Comfort Systems HVAC can help prevent both of these situations, because a good cleaning, inspection and filter change is a terrific way to keep your system running at its best!

The Air Conditioning 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 conditioning stinks like urine, it could be due to a variety of factors. One possible cause is a accumulation of bacteria or mold in the air conditioning system. This can happen if moisture accumulates in the system and creates a moist environment that can promote bacterial growth. The bacteria can create a foul odor that it similar to urine.

Another potential cause of the smell could be a clogged drain line. The condensation that forms inside the air conditioning unit needs to drain away correctly, but if the drain line becomes choked with debris, it can cause water to back up and collect inside the unit. This can produce a musty smell that is sometimes described as smelling of urine.

Your AC Smells Like Burning Plastic

If your AC smells like burning plastic, it might be because of an electrical problem 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 that somehow got in the HVAC system. If something foreign gets caught in the air conditioning system, it can become hot and emit a smell like burning plastic.

If you think you smell burning plastic coming from your air conditioner, it’s important to contact a professional right away.

Your AC Smells Like Gas

If your AC smells like gas, there could be a natural gas leak in the unit or in another part of your home. Natural gas has a distinct aroma, often described as smelling like rotten eggs or sulfur. That’s because this scent is incorporated into natural gas to make it easily detectable.

As we said previously, a natural gas leak can be VERY hazardous and calls for immediate attention. If you suspect a gas leak, turn off your air conditioning system, open windows and doors to air out the home, evacuate the building and contact your gas company or emergency services right away.

My Air Conditioner Smells Like Fish

If your air conditioner 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 fosters the growth of bacteria and mold. This can cause a strong odor that is often described as smelling like fish or, as mentioned earlier, it also can create 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 is possible 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 inspect and clean your air conditioning system. They can determine the source of the smell and take the proper steps to remove any contaminants and keep the problem from recurring.

My Air Conditioner Smells Like Vinegar

There could be numerous reasons an air conditioning system smells like vinegar. One possible cause is a dirty air filter. Another possible cause of the smell could 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 beneficial 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 diagnose 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 looking to upgrade, Indoor Comfort Systems HVAC can help locate the right unit to fit your home’s needs. We deliver dependable, expert air conditioner installation in Croydon.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is emitting out of your air conditioning equipment, it could be the result of a refrigerant leak. When the refrigerant leaks, it can create a chemical odor that is often described as smelling like chemicals or paint thinner, vinegar or acetone.

An additional possible reason for the smell could be something wrong with the electrical wiring or parts 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 concern, it's important to shut down your air conditioning system immediately and contact a professional to inspect and repair the unit. Refrigerant leaks can be harmful and may require immediate attention to prevent injury or damage to your home.

Weird Smells Coming from Your AC? Contact the Experts at Indoor Comfort Systems HVAC

If your air conditioner reeks and you aren’t able to fix it smoothly on your own, contact the cooling specialists at Indoor Comfort Systems HVAC. We have years of experience working with a wide variety of cooling systems. Our crew has fixed many air conditioning problems over the years—including funky smells. Call us today for quality AC repair in Croydon!