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

Depending on the cause of the odor, the root of the problem might be bacteria or fungus in the system. On the other hand, it could also indicate something mechanically wrong with the AC. Some smells are a warning of an unsafe situation, such as a natural gas leak.

At Forster Heating, we have a nose for these sorts of things. If you smell something weird coming from your air conditioner, chances are our team of skilled professionals has smelled it, too—and fixed it! We’ve earned the reputation as the premier company for air conditioning repair in Auburn.

What does a particular smell billowing coming from your air conditioning mean? Here are several frequent air conditioner aromas and what they might mean:

My Air Conditioner 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 growth of bacteria and fungus. This can cause a bad odor that is often described as smelling like feet.

Another potential cause of the smell could be a dirty air filter. If an air filter becomes clogged with dirt, dust and other contaminants, it can result in poor air quality and a musty smell that resembles feet.

To correct this dilemma, 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 replace the air filter regularly to promote good air quality and prevent the growth of bacteria and fungus.

Your AC Smells Like Rotten Eggs

If your air conditioning unit reeks of rotten eggs, it could be the result of a natural gas leak in the unit or in the surrounding area. Natural gas has a distinctive odor, often described as smelling like rotten eggs or sulfur, that is 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, get everyone out of the building and call your gas company or emergency services right away.

Your AC Smells Like Mildew

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

Another possible explanation for the smell might be a dirty air filter. If the air filter becomes clogged, it can result in poor air quality and a musty smell that resembles mildew.

Routine air conditioning maintenance from Forster Heating can help protect against both of these issues, because a good cleaning, inspection and filter change is a terrific way to keep your system working at its best!

The Air Conditioning 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 conditioner reeks of urine, it could be due to a variety of factors. One likely cause is a collection of bacteria or mold in the your cooling system. This can happen if moisture accumulates in the system and creates a damp environment that favorable for bacterial growth. The bacteria can emit a foul odor that is like urine.

Another possible 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 choked with debris, it can cause water to back up and accumulate inside the unit. This can create a musty smell that can stink like urine.

Your AC Smells Like Burning Plastic

If your air conditioner smells like burning plastic, this could indicate an electrical concern with the unit. Over time, the electrical parts in the air conditioning system can wear out or bust, which can make a burning smell that resembles plastic.

Another possible root cause of the smell could be a foreign object that somehow got in the HVAC system. If something foreign gets stuck in the air conditioning system, it can become hot and result in a smell similar to burning plastic.

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

My Air Conditioner Smells Like Gas

If your air conditioner 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 similar to rotten eggs or sulfur. That’s because an odor is added to natural gas so that it is easily detectable.

As mentioned earlier, a natural gas leak can be VERY harmful and needs immediate attention. Should you suspect a gas leak, turn off your air conditioning system, open windows and doors to air out the home, leave the building and contact your gas company or emergency services right away.

My Air Conditioner Smells Like Fish

Should your AC 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 is conducive to the growth of bacteria and mold. This can cause a strong odor that is sometimes described as smelling like fish or, as mentioned earlier, it also can result in a smell like dirty feet.

Another plausible explanation for the smell could be a dead animal or other biological material trapped inside the air conditioning system. This often can happen if an animal such as a mouse or bird becomes trapped inside the unit and dies.

To fix the issue, it's important to have a professional examine and clean your air conditioning system. They will be able to find the source of the smell and take the correct steps to remove any contaminants and stop the problem from recurring.

Your AC Smells Like Vinegar

There could be several reasons a home's AC smells like vinegar. One possible cause of the smell could be a clogged air filter. A second likely cause of the smell may be a refrigerant leak. Sometimes after the refrigerant leaks, it can make a chemical odor that is similar to vinegar.

To fix the issue, it's essential to have a skilled specialist inspect and clean your air conditioning.  If the odor continues after the cleaning and exchanging the air filter, it's best to reach back out to a professional to find and repair any persistent issues with your air conditioning. Or, the mechanic can tell you if your air conditioning ought to be replaced.

If you are planning to upgrade, Forster Heating can help select the right unit to fit your home’s needs. We provide dependable, skilled air conditioner installation in Auburn.

My Air Conditioner Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning unit, it could be due to 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 reason for the smell could be a problem with the electrical wiring or elements 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 shut down your air conditioning system as soon as possible and contact a professional to inspect and repair the unit. Refrigerant leaks can be dangerous and may require immediate attention to protect against injury or damage to your house.

A Nasty Odor Coming from the Air Conditioning? Contact the Experts at Forster Heating

If your air conditioner reeks and you aren’t able to fix it simply on your own, reach out to the cooling professionals at Forster Heating. We have years of experience working with a wide variety of cooling systems. Our crew has fixed a multitude of air conditioning troubles throughout the years—including strange smells. Call us today for quality AC repair in Auburn!