Why Your Air Conditioner Smells and How to Fix It

When your air conditioner starts spewing unusual or unappealing odors, it is necessary to take notice because it could be a sign of a major problem. Ignoring unpleasant smells coming from your air conditioning may lead to additional damage to your AC or even pose a risk to your health and safety.

Depending on the cause of the odor, the cause may be bacteria or fungus in the system. Other times, it could also signal something mechanically wrong with the air conditioning system. Some smells are a sign of a hazardous situation, including a natural gas leak.

At Walter's-Eaton's Electric, Plumbing, Heating & AC, we are experienced at getting to the root cause of stinky smells. If you smell something odd coming from your AC, there's a good chance our team of talented specialists has smelled it, too—and fixed it! We’ve earned the reputation as the go-to team for air conditioning repair in Ellsworth.

What does a specific odor billowing from your cooling system mean? Here are several typical air conditioner smells and what they may mean:

Your AC Smells Like Feet

If your air conditioner smells like feet, it could be caused by a buildup of bacteria or fungus inside of it. When moisture accumulates inside the unit, it can produce an environment that is beneficial to the development of bacteria and fungus. This can produce a foul odor that is often described as smelling like stinky feet.

Another possible explanation for an odor of stinky feet might be a dirty air filter. When your HVAC system's air filter becomes choked with dirt, dust and other debris, it can result in low air quality and a musty smell that it similar to the smell of feet.

To correct this unpleasant situation, 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 on a regular basis to ensure good air quality and protect against the growth of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioning equipment stinks like rotten eggs, it may 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 extraordinarily dangerous and requires immediate attention. If you suspect a gas leak, turn off your air conditioning system, immediately open windows and doors to allow gas to escape the area, evacuate the building and call your gas company or emergency services right away.

My Air Conditioner Smells Like Mildew

If your cooling system is giving off an odor like mildew, it could be due to a accumulation of moisture inside the unit. When moisture forms 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 cause of the smell may be a soiled air filter. If the air filter becomes clogged, it can lead to poor air quality and a musty smell that resembles mildew.

Regular air conditioning maintenance from Walter's-Eaton's Electric, Plumbing, Heating & AC can help avoid both of these issues, 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 undesirable things is when the air coming out of your HVAC system smells like urine.

If your air conditioner smells like urine, it could be traced back to a number of things. One potential cause is a buildup of bacteria or mold in the your cooling system. 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 create a foul odor that it similar to urine.

Another feasible 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 filled with debris, it can cause water to back up and build up inside the unit. This can generate a musty smell that resembles urine.

The Air Conditioning Smells Like Burning Plastic

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

Another possible root cause of the smell could be a foreign object that somehow got in the the air conditioner. If something foreign gets caught in the air conditioning system, it can get hot and emit a smell like burning plastic.

If you notice something that smells like burning plastic coming from your air conditioner, it’s worthwhile to phone a professional right away.

Your AC Smells Like Gas

If your AC smells like gas, it could be due to a natural gas leak in the unit or in your home. Natural gas has a distinct odor, often described as smelling similar to rotten eggs or sulfur. That’s because this scent is put into natural gas so that it is easily detectable.

As mentioned previously, a natural gas leak can be VERY dangerous 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 phone your gas company or emergency services straight away.

Your AC Smells Like Fish

If your air conditioning equipment smell like fish, it could be due to a build-up of bacteria or mold in the unit. Moisture causes an environment that promotes the growth of bacteria and mold. This can cause a disgusting 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 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 worthwhile to have a professional check out and clean your HVAC system. They can determine the source of the smell and take the correct steps to remove any contaminants and stop the problem from recurring.

Why My Air Conditioner Smells Like Vinegar

There could be numerous reasons your AC smells like vinegar. One possible cause of the smell could be a dirty air filter. One other possible cause of the smell may be a refrigerant leak. If the refrigerant leaks, it can make a chemical odor that is described as smelling of vinegar.

To fix the issue, it's beneficial to have a skilled mechanic examine 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, they can tell you if your air conditioning ought to be replaced.

If you are planning to upgrade, Walter's-Eaton's Electric, Plumbing, Heating & AC can help locate the right unit to fit your home’s needs. We offer reliable, expert air conditioner installation in Ellsworth.

The Air Conditioning Smells Like Chemicals

If the smell of chemicals is coming out of your air conditioning unit, it could be the result of a refrigerant leak. If the refrigerant leaks, it can create a chemical odor that some people describe as smelling like chemicals or paint thinner, vinegar or acetone.

Another possible cause of the smell could be an issue 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 think your system has a refrigerant leak or an electrical issue, 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 residence.

A Nasty Odor Coming from the Air Conditioning? Call the Pros at Walter's-Eaton's Electric, Plumbing, Heating & AC

If your air conditioner stinks and you aren’t able to fix it simply on your own, reach out to the cooling professionals at Walter's-Eaton's Electric, Plumbing, Heating & AC. We have plenty of experience working with a wide variety of cooling systems. Our crew has fixed many air conditioning troubles throughout the years—including funky smells. Call us today for quality AC repair in Ellsworth!