Why Your Air Conditioner Smells and How to Fix It

When your air conditioner starts emitting weird or unappealing smells, it is necessary to take notice because it could be a sign of a major problem. Ignoring unpleasant smells coming from your air conditioner may 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. Other times, it could also indicate something mechanically wrong with the air conditioner. Some smells are even indicative of a harmful problem, like a natural gas leak.

At Three Rivers Heating and Cooling, we are skilled at diagnosing and fixing these type of problems. If you smell something weird coming from your AC, you can bet that our team of skilled pros has smelled it, too—and fixed it! We’ve earned a reputation as the premier company for air conditioning repair in Portland.

What does a specific odor wafting out of your cooling system mean? Here are some frequent air conditioner aromas and what they may mean:

The Air Conditioning Smells Like Feet

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

Another potential cause of the stench of dirty feet could be a dirty air filter. If an air filter becomes filled with dirt, dust and other particles, it can lead to substandard air quality and a musty smell that bears a resemblance to feet.

To correct this issue, it’s important to have a professional 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 protect against the growth of bacteria and fungus.

Your AC Smells Like Rotten Eggs

If your smells like rotten eggs, it may be caused by 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, which is because of a substance added to it to make it easily detectable.

A natural gas leak can be 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, get everyone out of the building and call your gas company or emergency services at once.

Your AC Smells Like Mildew

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

Another possible reason for the smell could be a soiled air filter. When the air filter becomes clogged, it can result in poor air quality and a musty smell that has a resemblance to mildew.

Regular air conditioning maintenance from Three Rivers Heating and Cooling can help avoid both of these problems, because a good cleaning, inspection and filter change is a terrific way to keep your system working at its best!

My Air Conditioner Smells Like Urine

One of the most distressing situations is when your AC smells like urine.

If your air conditioning stinks like urine, it could could be caused by multiple factors. One possible cause is a accumulation of bacteria or mold in the your cooling system. This can happen when moisture accumulates in the system and creates a wet environment that favorable for bacterial growth. The bacteria can create a foul odor that it similar to urine.

Another feasible cause of the smell could be a blocked 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 accumulate inside the unit. This can produce a musty smell that is sometimes described as smelling of urine.

My Air Conditioner Smells Like Burning Plastic

If your air conditioner smells like burning plastic, a possible cause could be an electrical issue with the unit. Over time, the electrical components in the air conditioning system can wear out or break, which can make a burning smell that resembles plastic.

Another possible reason for the smell could be a foreign object stuck in the unit. If something foreign gets caught in the air conditioning system, it can get hot and cause a smell like burning plastic.

If you notice something that smells like burning plastic coming from your AC unit, it’s worthwhile to call a professional right away.

The Air Conditioning 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 recognizable odor, often described as smelling like rotten eggs or sulfur. That’s because an odor is put into natural gas to make it easily detectable.

As we said previously, a natural gas leak can be VERY harmful and requires 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 phone your gas company or emergency services straight away.

Your AC Smells Like Fish

Should your air conditioner smell like fish, it could be due to a build-up of bacteria or mold in the unit. Moisture creates an environment that is conducive to the growth of bacteria and mold. This can cause a strong odor that can be described as smelling like fish or, as mentioned earlier, it also can result in a smell like dirty feet.

Another possible cause of the smell could be a dead animal or other biological material trapped in 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 fix the issue, it’s important to have a professional inspect and clean your cooling system. They should be able to find the source of the smell and take the correct steps to remove any contaminants and prevent the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be multiple reasons a home’s air conditioner smells like vinegar. One possible cause is a plugged air filter. A second possible cause of the smell may be a refrigerant leak. If the refrigerant leaks, it can generate a chemical odor that is described as smelling of vinegar.

To fix the issue, it’s essential to have a skilled tech look at and clean your air conditioning.  If the odor lingers after the cleaning and changing 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 should be replaced.

If you are planning to upgrade, Three Rivers Heating and Cooling can help select the correct unit to fit your home’s needs. We offer dependable, professional air conditioner installation in Portland.

The Air Conditioning Smells Like Chemicals

If the smell of chemicals is emitting 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 some people describe as smelling like chemicals or paint thinner, vinegar or acetone.

One other possible source of the smell could be an issue with the electrical wiring or components inside the air conditioning system. This can result in a burning smell that is like chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical issue, 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 hazardous and may require immediate attention to avoid injury or damage to your house.

Weird Smells Coming from the Air Conditioning? Contact the Experts at Three Rivers Heating and Cooling

If your air conditioner reeks and you aren’t able to fix it simply on your own, call the cooling experts at Three Rivers Heating and Cooling. We have plenty of experience working with a wide variety of air conditioning systems. Our crew has fixed many air conditioning troubles through the years—including strange smells. Call us today for quality AC repair in Portland!