How To Clean Mold From Air Conditioner Vents

How To Clean Mold From Air Conditioner Vents featured photo

I’m a notorious cleaner. I especially cannot stand any mold growth in any area of my house. I have asthma so I take special measures in how I clean mold from my home’s air conditioner vents.

To clean and remove mold from AV vents, you need to unscrew and remove them. Soak them for about 15 minutes in your choice of mold-cleaning solution. Then, scrub or simply rinse away any remaining residue. Dry them well before putting the vents back in.

Mold is a serious and dangerous health risk if not dealt with. There are a variety of ways you can clean and remove them. What I have below is a general guideline on how you can deal with the issue and feel free to adjust them according to your needs.

In this article, I will dive into mold growth on air conditioner vents, how to tell if you’re dealing with one, and how you can solve the issue.

What is Mold?

The Center for Disease Control and Prevention (CDC) explains that mold is a fungal growth commonly found in various damp areas or decaying organic matter.

There are many kinds and species of mold. They can come in different colors from green, white, yellow, and black mold.

Indoor mold is generally caused by dampness and excess moisture. Mold thrives in moist environments and where there is excess moisture, you can expect mold growth.

Mold spreads through tiny mold spores. These tiny spores float in the air until they find a damp or moist surface to land on. Once they do, they will stick to that area and form new mold growth.

Is it dangerous on air conditioner vents?

Indoors, one common area many homeowners have to deal with mold growth is on air conditioner vents.

Though this is common in many homes, it still needs to be dealt with. Mold growth on your AC vents can be very dangerous.

This is exposing yourself, your family, and anyone who comes into your home to air-infested mold.

Breathing in mold can lead to a variety of health concerns:

  • Respiratory issues,
  • Asthma-like symptoms,
  • Headaches and dizziness,
  • Coughing and wheezing,
  • Allergy-like symtoms,
  • Nausea and fatigue,
  • Shortness of breath,
  • Eye irritation and itchiness,
  • Irritated sinuses and runny nose, and
  • Irritated and scratchy throat.

If left alone and not dealt with, these symptoms and existing health conditions can worsen.

Spotting Mold on Air Conditioner Vents

Mold is dangerous, especially if not removed. The good news is, mold can be pretty easy to spot and identify.

You should be concerned about mold growth on your air conditioner ducts and vents if:

  • You notice any moldy, damp, wet, or musty smell every time you turn on your AC;
  • You experience irritation and allergy-like symptoms affecting the eyes, nose, and throat whenever the air conditioner is on;
  • You experience nausea, headaches, or dizziness in the room with the AC on; and
  • There are visible mold or dark spots on the AC vents, ducts, and drip pans.

If you notice or experience any of the signs listed above, it’s time to inspect mold growth on your HVAC system.

What Causes Mold on Air Conditioner Vents?


Moist and damp environments are breeding grounds for molds. When an air conditioner unit is turned on, moisture forms on the air ducts. Air vents are damp and moist places, thus mold is a common issue.

As the AC unit circulates cold air to fight off the warm air, moisture accumulates on the air vents and it becomes susceptible to mold.

Oversized AC unit

Large AC units can cool off small spaces too quickly and turn off before dehumidifying the air in the area. This causes even more excess moisture, making the AC vents a more desirable environment for mold growth.

AC is too cold

When your air conditioning unit is set at a temperature too cold than it needs to be, this forms condensation on the air vents, which then leads to mold growth.

Dust and dirt

Dust and dirt can also collect on air vents and molds love these and consider them a food source. These along with other factors create a perfect environment for mold to grow.

How To Clean Mold From Air Conditioner Vents

Step 1: Protect yourself first before you clean

Before you charge through and start cleaning your vents, you need to put yourself first. Protect yourself from any mold contact or inhalation. Wear protective gloves, a mask, and protective glasses to protect yourself.

Step 2: Turn off the AC unit

For safer access to the unit and air vents, make sure the unit is first turned off before tampering with anything and attempting to clean it.

Step 3: Unscrew and remove the vents

Get a screwdriver and unscrew the vents. You will have a more successful attempt to clean the vents if you unscrew and remove them instead of reaching from where it’s screwed.

Step 4: Choose your cleaning solution

There is an array of cleaning solutions you can choose from to clean your AC vents. For one, there are many options of mold cleaning solutions readily available online.

If you don’t want to spend on commercial cleaning solutions, you can always make your own cleaning solution. Below are some of the most recommended:

  • One cup of water, one tablespoon of detergent, and half a tablespoon of baking soda
  • One part bleach and 16 parts water

For the DIY solutions above, adjust ratios according to how much of the solution you’re making.

Simple laundry detergent or dish soap could also be used if you don’t want to mix a solution. Learn more about cleaning window air conditioners without removing them.

Step 5: Clean with the solution and soak the vents to remove mold

To get on to the actual cleaning of the vents, there are no strict steps to follow. You only need to make sure you clean both sides of the vents.

You can spray down the vents with a garden hose to remove any mold residue first.

Then on a basin, pour your cleaning solution in. Soak the vents in the solution for about 15 minutes. Or you can forego the basin altogether and get a spray bottle instead. Put the cleaning solution inside and spray generously on the vents. Let it soak.

Step 6: Don’t forget to wipe down and clean inside the unit

There could be dust, dirt, and mold on the insides of the AC unit. Don’t forget to clean and wipe them down as well while you wait for the vents to finish soaking.

Step 7: Rinse and dry the vents

After 15 minutes of soaking the vents in the cleaning solution, rinse them.

If you’re not satisfied with the mold removal after soaking the vents,  go ahead and scrub the mold away.

Once all residues are gone, dry them well.

Step 8: Put the vents back

Screw everything back in place and try turning on the AC again.

Preventing Mold on Air Conditioner Vents

Now that you’ve gone through all the trouble of getting rid of mold on your air conditioner vents, you’d want to keep them away at all costs.

Invest in EPA-registered mold growth inhibitors

Get yourself a mold growth inhibitor. This will let you control mold growth on your AC vents.

Dehumidify your home

As mold thrives and grows in humid and damp environments, you’d want to control your home’s humidity levels with a dehumidifier. And because an AC unit naturally dehumidifies, you’d want to use a dehumidifier only when the AC is off.

Replace filters

Clean and maintain your AC unit by regularly replacing the air filters. This ensures no dust or dirt is trapped inside.

Clean and maintain drip pans

Drip pans collect water and moisture and this can be the very place molds thrive in. Make sure you regularly empty and clean them out to prevent this. These are common on portable air conditioners.

Regularly clean vents and air ducts

Have regular cleaning schedules to maintain and prevent mold growth on your vents and air ducts. Remember, prevention is better than cure!

Keep an eye out for signs of mold infestation

We’ve talked about signs that there could be mold infestation on your AC vents. After cleaning them, keep an eye out for these signs. If you notice any of them again – even one – immediately check out your vents and cut the growth right from the start.


Mold growth is a common issue when it comes to air conditioner vents. They’re common, yes, but that doesn’t mean we should just leave them be. They can be huge health risks so getting rid of them should be a priority.

To clean mold from AC vents, you’d need to get a mold-cleaning solution. Simply spray and soak the vents in the solution after removing them. After soaking for about 15 minutes, rinse and dry them before putting them back in.

And that was my guide on how to clean mold from air conditioner vents. If you have more questions, hit me up right below!