Why Your Air Conditioner Smells and How to Fix It

When your air conditioner starts spewing unusual or gross 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 could lead to serious damage to your HVAC system or even pose a risk to your health and safety.

Depending on the smell, the culprit may be bacteria or fungus in the system. On the other hand, it could also indicate something mechanically wrong with the air conditioner. Some smells are a warning of a dangerous problem, such as a natural gas leak.

At Indoor Comfort Systems HVAC, we are experienced at getting to the root cause of stinky smells. If you smell something odd coming from your AC, chances are our team of skilled professionals has smelled it, too—and fixed it! We’ve earned the reputation as the first call for air conditioning repair in Croydon.

What does a particular smell coming out of your AC mean? Here are several typical air conditioner smells and what they might mean:

Your AC Smells Like Feet

If your air conditioner smells like feet, it may 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 cause a bad odor that is often described as smelling like dirty feet.

Another likely cause of an odor of stinky feet may be a dirty air filter. If an air filter becomes choked with dirt, dust and other particles, it can cause poor air quality and a musty smell that it similar to the smell of feet.

To fix this issue, 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 exchange the air filter regularly to ensure good air quality and protect against the growth of bacteria and fungus.

Your AC Smells Like Rotten Eggs

If your air conditioner stinks like rotten eggs, it may be due to a natural gas leak in the unit or in the surrounding area. Natural gas has a unique 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 ventilate the area, evacuate the building and call your gas company or emergency services right away.

Your AC Smells Like Mildew

If your cooling system emits a smell like mildew, it could be due to a accumulation of moisture inside the unit. When moisture collects inside an air conditioner, it can cultivate the growth of mold and mildew. This can cause a musty odor that resembles mildew.

Another possible cause of the smell could be a soiled air filter. If 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 avoid both of these situations, 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 unpleasant situations is when your AC smells like urine.

If your air conditioning equipment stinks like urine, it could could be caused by multiple factors. One likely 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 wet environment that can promote 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 properly, but if the drain line becomes choked with debris, it can cause water to back up and build up inside the unit. This can create a musty smell that can stink like urine.

Your AC Smells Like Burning Plastic

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

Another possible reason for the smell could be a foreign object lodged in the HVAC system. If something foreign gets trapped in the air conditioning system, it can become hot and emit a smell similar to burning plastic.

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

The Air Conditioning Smells Like Gas

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

As we said before, a natural gas leak can be VERY dangerous and calls for immediate attention. When you suspect a gas leak, turn off your air conditioning system, open windows and doors to air out the home, get everyone out of the building and call your gas company or emergency services as soon as possible.

My Air Conditioner Smells Like Fish

When 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 produces 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 possible cause of the smell could be a dead animal or other biological material caught in the air conditioning system. This often is possible 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 check out and clean your cooling system. They should be able to determine the source of the smell and take the correct steps to remove any contaminants and keep the problem from recurring.

My Air Conditioner Smells Like Vinegar

There could be numerous reasons a home’s air conditioning system smells like vinegar. One possible cause of the smell could be a dirty air filter. A second possible cause of the smell might be a refrigerant leak. If the refrigerant leaks, it can create a chemical odor that is similar to vinegar.

To fix the issue, it’s beneficial to have a skilled specialist inspect and clean your air conditioning.  If the odor persists after the cleaning and replacing of the air filter, it’s best to reach back out to a professional to find and repair any underlying issues with your air conditioning. Or, they can tell you if your air conditioning should be replaced.

If you are looking to upgrade, Indoor Comfort Systems HVAC can help select the ideal unit to fit your home’s needs. We offer dependable, professional air conditioner installation in Croydon.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning equipment, it could be caused by a refrigerant leak. In a situation where 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 cause of the smell could be a problem with the electrical wiring or elements inside the air conditioning system. This can result in a burning smell that resembles chemicals or burning plastic.

If you believe there is a refrigerant leak or an electrical concern, it’s important to shut off your air conditioning system right away and contact a professional to inspect and repair the unit. Refrigerant leaks can be dangerous and may require immediate attention to avoid injury or damage to your house.

A Nasty Odor Coming from the Air Conditioning? Contact the Experts at Indoor Comfort Systems HVAC

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