man cleaning an HVAC unit

When your air conditioner starts emitting unusual or gross aromas, it is important to take notice because it could be a sign of a major 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 the cause of the odor, the cause could be bacteria or fungus in the system. Other times, it could also sign something mechanically wrong with the air conditioning system. Some smells are a sign of a harmful situation, including a natural gas leak.

At Bishop’s HVAC, we are experienced at getting to the root cause of stinky smells. If you smell something odd coming from your cooling system, there's a good chance our team of qualified specialists has smelled it, too—and fixed it! We’ve earned a reputation as the first call for air conditioning repair in Sacramento.

What does a specific odor billowing out of your cooling system mean? Here are some typical air conditioner odors and what they may mean:

The Air Conditioning Smells Like Feet

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

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

To solve 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 regularly to provide good air quality and restrict the development of bacteria and fungus.

My Air Conditioner Smells Like Rotten Eggs

If your air conditioner smells 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 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, make everyone leave the building and call your gas company or emergency services at once.

My Air Conditioner Smells Like Mildew

If your air conditioner emits a smell like mildew, it may be due to a collection of moisture inside the unit. When moisture accumulates inside an air conditioner, it can cultivate the growth of mold and mildew. This can cause a musty stench that bears a resemblance to mildew.

Another possible cause of the smell might be a clogged air filter. Once the air filter becomes clogged, it can cause poor air quality and a musty smell that resembles mildew.

Annual air conditioning maintenance from Bishop’s HVAC can help avoid both of these situations, because a good cleaning, inspection and filter change is a very good way to keep your system running at its best!

Your AC Smells Like Urine

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

If your air conditioning equipment reeks of urine, it could be due to a variety of factors. One potential cause is a accumulation of bacteria or mold in the your HVAC. 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 is like urine.

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

Your AC Smells Like Burning Plastic

If your air conditioning system smells like burning plastic, it might be because of an electrical concern with the unit. After a while, the electrical components in the air conditioning system can wear out or malfunction, which can make a burning smell that resembles plastic.

Another possible cause of the smell could be a foreign object stuck in the HVAC system. If something foreign gets stuck in the air conditioning system, it can become hot and cause a smell like burning plastic.

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

The Air Conditioning Smells Like Gas

If your AC smells like gas, it could be due to a natural gas leak in the unit or in the surrounding area. Natural gas has a distinctive smell, often described as smelling like rotten eggs or sulfur. That’s because a smell is put into natural gas to make it easily detectable.

As mentioned previously, a natural gas leak can be VERY dangerous and needs 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

Should your AC smell like fish, this could be a sign of 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 create a smell like dirty feet.

Another possible cause of the smell could be a dead animal or other biological material trapped inside the air conditioning system. This often can take place if an animal such as a mouse or bird is trapped inside the unit and dies.

To correct the issue, it's often necessary to have a professional examine and clean your cooling system. They will 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 numerous reasons an AC smells like vinegar. One possible cause might be a plugged air filter. One other likely cause of the smell could be a refrigerant leak. When the refrigerant leaks, it can create a chemical odor that resembles vinegar.

To fix the issue, it's important to have a skilled mechanic examine and clean your air conditioning.  If the odor continues after the cleaning and replacing of the air filter, it's best to reach back out to a professional to identify and repair any hidden issues with your air conditioning. Or, the mechanic can tell you if your air conditioning needs to be replaced.

If you are wanting to upgrade, Bishop’s HVAC can help select the right unit to fit your home’s needs. We offer dependable, expert air conditioner installation in Sacramento.

Your AC Smells Like Chemicals

If the smell of chemicals is coming from your air conditioning equipment, it could be due to a refrigerant leak. When the refrigerant leaks, it can create a chemical scent that people sometimes describe as smelling like chemicals or paint thinner, vinegar or acetone.

An additional possible cause of the smell could be problems with the electrical wiring or elements inside the air conditioning system. This can cause a burning smell that is like chemicals or burning plastic.

If you suspect a refrigerant leak or an electrical problem, it's important to shut off 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.

Strange Smell Coming from Your AC? Call the Pros at Bishop’s HVAC

If your air conditioner stinks and you aren’t able to fix it quickly on your own, contact the cooling professionals at Bishop’s HVAC. We have years of experience working with a wide variety of cooling systems. Our crew has fixed a multitude of air conditioning problems over the years—including strange smells. Call us today for quality AC repair in Sacramento!