How To Prevent Mold In Window Air Conditioner?

Helen Skeates
Helen Skeates
16 min read

Keep an eye out for mold in window air conditioners when you’re taking care of your AC. You’ll need to keep an eye on variables like relative humidity and wetness to see how they affect the efficiency of your unit and the quality of the air it produces. If you have mold in your air conditioner, you’ll want to read this article because we’ll explain where it comes from and what you can do to get rid of it.

Why Is Mold Growing In My Window Air Conditioner?

Mold thrives in damp environments, and this is the most common truth about the fungus. Mold thrives under these conditions, making your air conditioner a perfect growing site.

How to Prevent Mold In Your Window Air Conditioner | Feldco Peoria

In addition, mold can disperse its spores to other parts of the house, posing a spread hazard. As an air conditioner functions, it’s possible that any mold that grows in the unit will travel to where you’ve placed it, lowering the room’s air quality.

Mold growth can also be aided by high humidity. Mold can grow in and around your air conditioner if the humidity in your location is high.

If you keep these tips in mind, you’ll be better prepared to deal with or avoid mold growth in your air conditioner.

What You Need To Know About Mold in a Window Air Conditioner

A window air conditioner and your health are likely on your mind if you’re reading this post (or if you’ve already had this experience personally!).

It’s wise of you to plan ahead. Allergic reactions and asthma, as well as other respiratory problems, are among the possible health impacts of mold exposure, according to the Environmental Protection Agency (“EPA”).

In addition, eliminating mold is the best method to extend the life of your a/c unit (and avoid a costly replacement) for years to come!

What Causes Mold in a Window Air Conditioner?

Moisture is the obvious answer. Simply because it removes moisture from the air as it operates, your window air conditioner is a prime candidate for mold growth (which is why you may occasionally hear a dripping sound coming from the unit).

Mold thrives in a moist, dark environment, and this unit’s ductwork is no exception. In addition, mold spores, which are minute and dispersed by the air, are the means through which mold reproduces.

Therefore, it’s better to avoid mold from growing within your a/c unit by taking preventive measures (the EPA recommends not even running an air conditioner that may have mold in it because it may spread spores throughout your home).

Step 1: Keep an eye on humidity

Mold thrives in moist environments, and humidity is a common contributor to that moist environment. In order to prevent the growth of mold, the CDC advises a humidity level of 30-60% for the home’s interior.

Dehumidifiers and window air conditioners have certain similarities, however window air conditioners aren’t very good at managing humidity when the relative humidity is more than 60 percent.

The Centers for Disease Control and Prevention recommends a dehumidifier if you find the air too damp even while the air conditioner is on.

Step 2: Don’t let your air conditioner idle

To prevent the growth of mold, it is essential to keep your window air conditioner running frequently after it has been installed.

Idling your air conditioner for long durations is a common mistake individuals do with their air conditioning equipment — think about when you’re on a beach vacation during the sweltering summer months!

Even though you may think you’re saving money by not operating your air conditioner, the lack of air flow through the unit can allow moisture to accumulate and eventually lead to mold growth.

You should instead leave your air conditioner on a low setting while you are away (or even better, taking the time to clean out the unit prior to leaving.)

Step 3: Remove dust from the unit

Mold spores can also be found in the dust that accumulates in your air conditioner. The filter and the unit itself are the most likely sites for dust to collect.

Running a hand-held vacuum or vacuum hose inside the air conditioner is all that is needed to get rid of any leftover dust.

Simply remove the front cover to have access to the AC unit’s interior. Generally, the front cover of an air conditioner is either “spring-loaded” so you can remove it with your hands or latches that you must release with your hands to remove the air conditioner. Getting the front cover off might require removing a few screws in the worst case situation.

Before attempting to reach the inside of your air conditioner, make sure it is unplugged!

As you work, be sure to take pictures of the unit so you have a record of how it originally appeared and fit together.

Step 4: Remove dust from the filter

It looks like a fine screen inside of a plastic frame for your air conditioner’s filter. It acts as a barrier to keep trash and air particles from entering the room.

The filter is a crucial component of the air conditioner, however mold can develop easily on the dust that accumulates on the filter.

Always located behind the front grill, this filter can be reused. When cleaning the filter, run a vacuum hose or hand-held vacuum over it to remove any dust (being careful not to damage the mesh screen).

To eliminate the dust, you can run the filter under water (but wait for it to dry before putting it back into the air conditioner).

Step 5: Regularly clean your air conditioner

Cleaning your air conditioning unit once or twice a month is the best method to keep it free of dust and moisture. Find out how to thoroughly clean your air conditioner by reading this informational article!

Cleaning Your Window AC Unit, Avoid Mold and Mildew

For more than merely cooling a room, window air conditioners are a household name. Black mold and mildew thrive in the unit’s vents, which few people know about.

In spite of the fact that condensation is expelled outside, it builds up around the ducts and coils and is ideal for the growth of mold that thrives in damp conditions.

It’s a lot more serious than most people realize when it comes to mold growth and production in their air conditioner. Invisible spores of mold are constantly circulating in the air. That’s why it’s so vital to clean your window air conditioner and keep it mold and mildew free.

Mold grows and spreads quickly and easily, and before you know it, it can spread and grow all over the place. It doesn’t take long for the mold to spread and grow throughout the house once this happens.

How To Clean Mold from Your Window Air Conditioner Safely - | Window air conditioner, Cleaning painted walls, Mold remover

How to Detect Mold in Your Window Air Conditioner

Basement mold, leaky roof regions, and damp carpets under old or previously wet carpets are all common occurrences for most residences. Some may be unaware of the threat lurking in their air conditioners.

In many cases, the initial indicator of mold is a musty odor that permeates the space without any visible evidence of active spores. Symptoms of mold exposure can begin to appear within a matter of days, and they can be life-threatening.

If you keep smelling this stench, you can rest convinced that there is mold in your house. Mold may be developing someplace, even if it’s not obvious where at first.

If the mold isn’t discovered early, the expense of extensive mold removal and rehabilitation might quickly rise. If the mold is discovered early enough and the homeowner takes action quickly, the danger can be controlled before it gets out of hand.

A thorough inspection or removing the filter and inspecting it could reveal obvious indications of mold in your air conditioner’s system. It may be too early to see active mold on or around the filter, but the smell of it is still present and should be investigated thoroughly.

Household Members Could Get Sick From Breathing Mold

Mold infection can mimic the symptoms of a cold or the beginnings of the flu in its victims. See your doctor right away if you or anyone else in your home begins to experience any of the following symptoms.

  • a throbbing pain in the throat
  • Headaches
  • Sneezing
  • Coughing
  • a feeling of breathlessness
  • Wheezing
  • Fatigue
  • Infections of the lungs
  • Feeling depressed and out

If you’ve noticed any of the above symptoms after using your air conditioner, there’s a strong possibility mold is to blame. Call All Hours Air if you’re unsure and we’ll send a technician out to conduct a full inspection.

It’s difficult to see mold spores when they’re small, but as the mold grows, it becomes more obvious to the naked eye. If you notice any of the symptoms described above in members of your family, don’t put it off any longer.

Rather than disappearing, the humidity that window units suck in from the outside air sits around and within the coils that keep the air cool. Mold spores thrive in conditions like these, when moisture, filth, and dust from the air combine to create an ideal growing and spreading environment.

Leaving it in place throughout the winter will just encourage mold growth because there will be no way to remove, clean, or cover it. As a result, mold, allergy, and asthma symptoms might develop as a result of a lack of proper filtering and cleaning of the HVAC system.

How to Clean Your Window Air Conditioning Unit

Keeping your air conditioner clean will help you avoid costly and time-consuming repairs in the future, as well as ensure that your A/C is reliable and efficient for many years to come.

All Hours Air recommends that you leave significant air conditioning cleaning and maintenance to the experts, but there are a few tips you can apply to maintain your A/C in good working order yourself.

Window Unit Cleaning Step by Step Guide

Remove the window unit’s power cord if it’s connected to the home’s electrical system. Turn off the primary breaker in the circuit box in this scenario. You’ll need the owner’s manual or the manufacturer’s phone number for the following step.

Verify that the Capacitor is properly discharged by consulting the owner’s manual. The component that retains the motor’s starting charge in reserve is known as a Capacitor. Before you begin the cleaning process, you need to make sure there are no remaining electrical charges.

After that, use a moist towel to wipe off the exterior of the case. Before opening the cover, be sure to clean it well with a strong dirt and grime remover.

It is possible to unsnap or remove the screws/plastic hooks that hold the front cover in place using your hands. The metal components should be handled with care due to the possibility of sharness.

Use hot soapy water to thoroughly clean the filter in your unit if that is possible. Use a soft brush to gently remove all of the dust and particles that have accumulated on the surface. Before reactivating the A/C, place the filter in an area where it can dry properly. Dirt and mold will be attracted to a wet filter if it is reinstalled.

Manufacturers recommend changing the disposable filter periodically to help prevent mold.

Vacuum the inside, bottom, back of the cover, sides, and metal grill, if the device has one, with an extension hose. A moist cloth can be used to remove heavy buildups of dirt and grime.

Reassembling it after it has dried completely is recommended. Activate it by reconnecting the power cord and turning it on. Once the power is restored to the vents, a little amount of debris and soot will be released.

You should keep your window air conditioner in a dry location during the winter to avoid accumulating dust and other debris. If you want to avoid costly repairs and prevent illness, call All Hours Air for a more thorough cleaning and servicing of your unit.

Is it time to upgrade to a new central air conditioning system? We can install or replace your air conditioning unit in Reno and Sparks.

Mold in Air Conditioners: How to Clean and Prevent Growth | Molekule Blog


Why is there mold in my window air conditioner?

Mold can grow in your window air conditioner, even if you’ve purchased the greatest one available. Vents can become clogged with dust, especially in the dead of winter. Mold can begin to develop and feed on dust particles if there is enough dampness.

Can you spray Lysol in window air conditioner?

Cleaning a window-mounted air conditioner is just as cost-effective as cleaning your own central air system. Coils on the rear of the device can be cleaned with Lysol® All-Purpose Cleaner.

Can I spray bleach in my window air conditioner?

To clean a window air conditioner, you can use bleach because it kills mold. In addition to damaging metal and other components of your air conditioning system, it is extremely dangerous.

Can black mold grow in window air conditioners?

Most of the time, air conditioners and HVAC ducts are not favorable environments for mold growth to occur. There is no food source for mold in the styrofoam and sheet metal ducting found inside window units. However, dust can accumulate in these areas, allowing mold to thrive.

What temperature should you keep your house to prevent mold?

Between 77 to 86 degrees Fahrenheit is considered optimum. Temperatures in the home can rise significantly during the summer months. During the summer, make an effort to keep your house at a cooler temperature. Mold is less likely to grow if the thermostat is set to the low 70s.

Is the black stuff in my AC mold?

Mold may be growing in your air conditioner’s vents. AC systems, particularly the interior AC unit, are frequently discovered to have mold growth. Mold thrives in a dark, moist environment like the inside of a refrigerator.

Why is there black stuff in my window air conditioner?

Black particles originating from your air conditioning vents are most likely: Candle or fireplace ashes (the most likely culprit) spores of mold. Dust or filthy insulation may be the cause.


When it comes to keeping mildew at bay in a window air conditioner, you’ll need to get your hands dirty. Investing in a healthier and happier household is well worth the effort. It’s a blessing in and of itself to be able to breathe clean air.

Helen Skeates

Helen Skeates

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