My Air Conditioner Smells. Is it Dangerous?

My Air Conditioner Smells. Is it Dangerous?

Why does my air conditioner smell and why blog post

Everyone is familiar with the sense of relief that overcomes you when your air conditioner turns on during a hot day. Unfortunately, that sense of relief can be extinguished by a foul odor that may be coming from your air conditioner.

Air conditioners can emit many different types of odors and may emit them for a multitude of different reasons. Not all the foul odors that can come from your air conditioner will smell the same. The different odors can usually help indicate to you exactly what is going awry with your air conditioner.

If your air conditioner smells like:

Dirty Socks

If your air conditioner turns on and causes your house to smell like a high school gym locker room you may have an issue with mold or mildew growth within your air conditioner.

Mold can grow on your air conditioners evaporator coil as it becomes dirty, and cause your home to have a very unpleasant, yet familiar musty smell. Other issues such as a clogged drain line may cause water to fill up and sit in the drain pan. Stagnant water combined with dirt, dust, bacteria, and darkness can allow mold to grow and cause the dirty sock smell to emit from the air conditioner.

In order for the problem to be resolved, you will need to have the coils cleaned and or replaced. Gaining access to the coils can be difficult and is best handled by a professional.

If there is too much dirt buildup, and cleaning the coils does not provide a long term solution then they will need to be replaced. Fortunately, most Air conditioning systems come with a 15 to 20-year warranty that covers evaporator and condenser coil replacements.

Sulfur/Rotten Eggs

The stench of rotting eggs coming from your air conditioner could be cause for some concern as it can indicate that you have a natural gas leak in your home. If this is indeed the case you will want to turn off your air conditioning unit, and open all doors and windows to allow the gas to leave your home (add the thing about contacting your A/C specialist).

Another possibility of a rotten egg smell coming from your air conditioning is that an animal has gotten into the air ducts within your home and has died, in which case you will want to have the animal removed as soon as possible.


Your air conditioner may be leaking refrigerant if there is a chemical smell coming from your unit.

Refrigerant is a unique chemical contained within the coils of your air conditioning unit and is used to help to cool and dehumidify your home. Over time these coils can break or crack releasing some of the refrigerants. The fumes from the refrigerant can travel through your air ducts causing your home to smell like chemicals or a sweet chloroform scent.

Reasons Your Air Conditioner May Smell

  • Stagnant water that is not draining properly within the air conditioning unit
  • Dirty coils within the air conditioning unit
  • Dead animals in the air conditioning
  • Natural gas leaking into the air conditioning system
  • Leaks from the air conditioning unit

Is air conditioner odor dangerous?

In most cases, air conditioner odor is not detrimental to your health in the short term and is more of a nuisance than anything. However, there are some odors you will want to be aware of as they may pose a threat to your health.

If your air conditioning is emitting an odor that can be described as rotting garbage there could be a natural gas leak somewhere in your home. In this case, the air conditioning is helping to circulate the natural gas throughout your home.

This can be dangerous as inhaling too much natural gas can lead to asphyxia, and if enough has been dispersed throughout your home then a spark can cause fires or even an explosion in your home. It is important to leave your home until the issue is resolved.

Another odor that you and your family should be wary of is the smell of dirty socks which indicates that there may be mold growth within your air conditioning system. Mold does not usually pose any immediate to your health, and common symptoms of exposure to mold spores are mild symptoms that include stuffy nose, wheezing, coughing and skin rashes.

Once you have confirmed that you have a mold problem you will want to get the problem resolved as quickly as possible as long term exposure to mold can be fatal. Molds produce mycotoxins and exposure to these toxins can harm your immune system, and even cause cancer.

Why does my air conditioner smell bad when turned on?

If your air conditioner does start producing a foul odor there is a good chance it has been a while since you have used it. This period of inactivity allows the source of the odor to go undetected, but once the air conditioning system is being used again the foul odor travels throughout your home via the air conditioning ducts.

If your ac system is causing you issues, call the best air conditioning company in San Antonio, Houston, and all of the areas in between.

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Texas Air Repair offers air conditioning, heating, and indoor air quality services to residential and commercial customers in San Antonio, TX & the surrounding areas with their 25+ years of experience.

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About Us

Texas Air Repair offers air conditioning, heating, and indoor air quality services to residential and commercial customers in San Antonio, TX & the surrounding areas with their 25+ years of experience.