Can Black Mold Grow in Window Air Conditioners?  

The last thing you want to find out is that the device that is sending conditioned air into your home is affected by mold. But, unfortunately, this can happen.

It is not uncommon for black mold to grow in window air conditioners – these units create moisture and they are quite dirty. Black mold is dangerous for your health, so you should get rid of it as soon as possible and try to prevent it from returning. 

Can Black Mold Grow in Window Air Conditioners?  

Your window air conditioner can become a breeding ground for black mold as it has plenty of water and ‘food’ – the greenish-black substance needs both of those to survive.

Mold spores are everywhere and it is practically impossible to get rid of them. At one point, these spores will make their way into your window air-con, and if there is food in the unit for the substance to thrive, then the spores will turn into black mold.

In order to grow, mold needs:

  • A wet environment – you wouldn’t have to add water to your air conditioner for it to function, but the unit will be creating moisture while running. This condensation then drips into a pan (and attracts mold).
  • Food – an air conditioner collects plenty of dust and other particles while operating. If you fail to follow a regular cleaning schedule, the dirt will accumulate inside the unit and will be used by the mold spores as a food source. 

Read: Why Window Air Conditioner All Lights Flashing And Beeping

What Is the Black Stuff in My Window Air Conditioner?

If you see a greenish-black substance inside your air-con, the chances are high that you’re dealing with black mold.

Sometimes, you might notice black dust coming out of your air conditioner if you have been using a fireplace or burning a candle (in such a case, it would be soot). 

What Kind of Mold Grows in Window Air Conditioners?

There are 6 common types of mold that can be found in window air conditioners:

  1. Black mold
  2. Fusarium 
  3. Acremonium
  4. Trichoderma
  5. Alternaria
  6. Mucor

The majority of these types are either white or green, but only Stachybotrys is a black mold.

Read: Why Window Air Conditioner Compressor Not Turning On?

Have a Question? Ask HVAC Technician

Click here to use the chatbox to speak with one of our technicians.
No in-home service calls. No appointments.

How Do I Know If My Window Air Conditioner Is Moldy?

It is relatively easy to figure out whether your window AC has mold in it or not. Look out for the following signs:

  • There is a musty odor that fills the room only when you have the air conditioner running
  • You or someone in the household are experiencing an ongoing allergic reaction, trouble breathing, or other respiratory problems
  • You can see patches of mold inside the air conditioner
  • There is black dust accumulating around the unit

What Does Black Mold Look Like in an Air Conditioner?

From the outside of the unit, black mold can look like black dust or relatively small spots that appear around the air-con. If the spots are challenging to wipe off and the substance has a slimy texture, then it is most certainly black mold.

If you choose to inspect the inside of the unit, you might find clusters or streaks of black or greenish-black stains. Turn the power to the unit off, remove the front cover, pull out the filter, and use a flashlight to search for these signs of mold growth. 

Read: Does A Window Air Conditioner Need A Dedicated Circuit?

What Does AC Mold Smell Like?

You’ll have a strong, distinct, musty smell fill up your room every time you turn on a window AC that has mold growing in it.

Can You Test Mold in the Air?

There are plenty of at-home mold testing kits available on the market nowadays. A lot of them would require you to collect a few surface samples and then send them to a lab.

You can go for kits with air sampling pumps that let you test the actual air for mold spores, but, in the majority of cases, you would still have to send the collection cassette to an accredited lab.

If you want to carry the test out on your own, then look for kits that come with Petri dishes and a growing medium – by using these things, you’ll be able to determine whether or not you have mold in only a few days. 

Read: Does A Window Air Conditioner Pull Air From Outside?

Can Mold in Window Air Conditioner Make You Sick?

Exposure to mold can actually make you sick, and black mold is considered to be one of the most dangerous types.

If you have noticed any of these symptoms, then it’s time to check your air conditioner for mold:

  • Wheezing
  • Throat irritation
  • Congestion
  • Difficulty breathing
  • Respiratory infections

The latter, in the worst-case scenario, may lead to pneumonia or Legionnaires’ disease. 

What Are Signs of Mold Sickness?

Some other symptoms of mold exposure include:

  • Nasal irritation
  • Itchy and watery eyes
  • Blurry vision
  • Coughing and sneezing
  • Nosebleeds
  • Headaches
  • Skin irritation
  • Asthma attacks

How Long Does It Take to Get Sick from Black Mold Exposure?

Some symptoms might first appear 2-9 hours after exposure. Of course, the exact terms are going to depend on a lot of factors – some people might not develop any symptoms at all.

Read: How To Prevent Mold In Window Air Conditioner?

How Do I Get Rid of Mold in My Window Air Conditioner?

Ideally, you would want to remove the AC and place the unit somewhere outside, so that you won’t get exposed to mold and the fumes from the detergents.

Don’t forget to wear protective eyewear, a face mask, and gloves when getting rid of mold.

Does Vinegar Kill Mold in Air Conditioner?

Vinegar is a natural mold inhibitor and disinfectant as it contains acetic acid. 

Simply mix equal parts of white vinegar and water in a spray bottle and apply the solution to the affected part of your air conditioner. In an hour or two, wipe the surface down.

Vinegar won’t harm your window air conditioner as long as you don’t apply it directly to the unit’s electrical components.

How Do You Clean Mold Out of a Window Air Conditioner Without Removing It?

Ideally, you would want to remove the air-con as this will allow you to clean the mold out more effectively.

If the parts of the unit that are affected by mold are easily accessible, you can try leaving the AC in the window and simply spraying the affected elements with a vinegar solution

How Do I Keep Black Mold from Growing in My Window Air Conditioner?

There are a few things that you would have to do to make sure that black mold never becomes a problem ever again:

  • If your AC has a humidity control setting, then turn it on
  • Try to get rid of any leaks as soon as possible
  • Keep the air conditioner free of dust (you can use the vacuum cleaner hose)
  • Deep clean the unit regularly 

Is It OK to Spray Water on Your Window Air Conditioner?

You can spray water and a vinegar-water solution on your AC if it needs cleaning. You should never submerge the unit in water, however.

Can I Spray Lysol in My Window Air Conditioner?

It is not recommended to spray any chemicals on your window AC as over time the metal parts might start to corrode. Lysol also contains ethanol which doesn’t go well with the electrical components in the air conditioner.

Do Window Air Conditioners Need to Be Cleaned?

Clean the air filter once a month and fully replace it once every 3 months. You also might want to dust the outside casing every week and wipe it down every month.