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How to Clean a Window Air Conditioner

How to Clean a Window Air Conditioner

We get to enjoy a nice cold breeze from our window air conditioner during the hot months of the years. But to keep up that experience, you need to maintain your air conditioner correctly.

Cleaning your window air conditioner is one way to maintain it and keep it in good working condition.

When the window AC isn’t blowing cold air, the evaporator and condenser coils are clogged. Over time these units develop dust, mold, and mildew, creating a health risk for people in the room. It will also reduce performance with time and increase energy use.

You’ll need a few supplies to clean your filter every month to ensure it runs at peak efficiency. Wipe the filter, brush the coils, and vacuum the interior. Here is our step-by-step guide on how to clean a window air conditioner.

What You Need

  • Safety clothing (N-95 respirator mask, safety goggles, and leather gloves)
  • Household cleaning solution in a spray bottle
  • Mold and mildew remover or hydrogen peroxide
  • Soapy water in a spray bottle
  • Microfibre cleaning cloth
  • Nylon brush
  • Shop-vac
  • Screwdriver


  1. Take safety precautions

  • Wear the safety goggle and respirator mask to avoid inhaling any dust, mold, or mildew when cleaning.
  • Switch off the air conditioning unit and unplug the power cord from the wall socket. It is an important safety measure to prevent electrocution.
  1. Clean the filter and front panel.

  • Unscrew the air conditioner from its position.
  • Remove the front panel to access the filters for their monthly cleaning. Use your fingers to unclasp the tabs on either side of the top of the front panel. Some models will require you to use a screwdriver to remove the front panel.
  • Carefully shake out the filter to get rid of loose dust and dirt.
  • Spray the sides of the filter and front grille cover with the household cleaner of your choice.
  • Let it soak for about 10 minutes, then use a microfibre cleaning cloth to scrub off the dirt.
  • Rinse the filter and panel thoroughly with a water hose.
  • You may have to spray and scrub the filter and rinse more times if necessary. It would be best if you stopped cleaning once the rinsing water is clear. If the filter is too dirty, you will have to get a replacement.
  • Place the filter and front panel aside to air dry.
  1. Clean the evaporation coil and interior surfaces.

  • Use a fin comb or a soft bristle brush to get rid of dust from the evaporator coil (the group of metal fins behind the filter). Be gentle when brushing since these metal fins are fragile and may also cut you. You should wear leather gloves to prevent cuts from the fins.
  • Use a shop vac to remove any remaining debris from the evaporation coil’s hard-to-reach areas and the unit’s interior.
  • Spray the entire interior of the air conditioner, including the drain pan, with the household cleaner and scrub with a coil brush or nylon brush, then repeat as needed. Scrub the fins downwards and not across to avoid damaging them. Furthermore, air conditioners can handle water, so do not worry about water spoiling the air conditioner’s components.
  • Wipe down the interior with a dry microfiber cloth. Be careful not to damage the fins. Remember to clean the drain pan well to prevent clogging the drain line and causing water damage.
  • Spray some cleaning solution on the exterior and wipe it down until it is clean.
  • Allow the fins and the filter to air dry, and then reassemble the air conditioner with the filter first and then snap the front panel back to its place.

How do you clean a window air conditioner without removing it?

The steps explained above are excellent when deep cleaning, but you may also want to clean your unit without removing it all the time, especially during daily maintenance. Here is how to clean your window air conditioner without removing it:

  • Turn off your window air conditioner and unplug it from the wall.
  • Remove the front panel to access the filter inside.
  • Soak your filter in a bucket filled with soapy water. Get a replacement if it is due for one. You should replace your air conditioner filter at least once every three months.
  • Scrub the filter, rinse and let it air dry.
  • Spray the interior of your air conditioner and the fins with hydrogen peroxide or mold and mildew remover.
  • Without applying too much pressure, brush the fins with a soft nylon brush to remove dirt.
  • Allow everything to dry completely before reassembling in case there is still moisture on the electrical components.

How do you clean mold out of a window air conditioner

If you notice a musty smell coming out of your unit, that is a sign of mold growing in your window air conditioner; usually due to moisture and dust or dirt. Mold is hazardous. It multiplies in the air and ends up causing respiratory issues when inhaled or worsens existing respiratory conditions.

Typically, there should be no mold on the Styrofoam in your window air conditioner because it cannot absorb moisture. However, if you hardly clean your unit and enough humidity collects on the Styrofoam surface, mold will thrive there. Follow the steps below to get rid of mold in your window air conditioner:

Things You Need

  • Screwdriver
  • 3% hydrogen peroxide or mold and mildew remover
  • Nylon brush


  • Turn off the air conditioner to prevent mold spores from further spreading into the room.
  • Remove the front grille cover, usually by snapping it off or unscrew it.
  • Grab a flashlight and inspect the extent of the spread of the mold. The signs of mold and mildew are usually brown, black, gray, or greenish spots. There may also be a musty smell from the interior.
  • Soak the front panel cover and the filter in a bucket of soapy water.
  • Remove the top and black cover of your unit according to the user manual.
  • Use a shop vac or a DustBuster to vacuum the dust from the interior of your unit.
  • Spray the interior of your unit with a household cleaning solution, and let it soak in for about 10 minutes.
  • Then spray it down with a garden hose or use a nylon brush to scrub the mold off.
  • Spray the interior of your unit with 3% hydrogen peroxide or mold and mildew remover to disinfect and kill any remaining mold.

NOTE: Do not use alcohol; it is flammable. And do not use bleach, it has toxic fumes, and it can also damage the unit components.

Prevention is better than cure. It is best to prevent mold from growing in your air conditioner by:

  • Avoid moisture by getting an air conditioner with humidity control. Set your unit on auto during summer or hotter months. If you don’t, warm, moist air builds up inside the air conditioner and creates an environment suitable for mold to thrive.
  • Clean and disinfect your air conditioner regularly to prevent dust and dirt from building up.
  • Service your unit twice annually by a professional. Mold can grow in the pipelines, which are areas you do not see during a deep clean. The mold spores can pass through leakages in the pipes and reach the air in the room.

If the mold infestation is too much, you will have to replace your unit.

How often should a window air conditioner be cleaned?

As a rule of thumb, you should clean your window air conditioner at least every two months to make sure the refrigerant is not all used up and disinfect to reduce mold build-up. If you reside in a dusty area or have pets around, you may have to clean it regularly. Additionally, a deep clean of the coils once every year should be enough. A deep clean gives the best results when you do it in the spring in preparation for summer use.

Check this too: How Long Does it Take for an Air Purifier to Clean a Room

If you stay in a dusty environment, you may have to do some basic daily cleaning. It is essential because such places pose a greater risk of clogging and overheating the window air conditioner due to dust entering the coil. Regularly cleaning your air conditioner improves the quality of air in the room.

Can you hose down a window air conditioner?

Yes, it is okay to spray water on a window air conditioner to clean it. It keeps the window air conditioner efficiently and ultimately lengthening its lifespan. A window air conditioner is relatively waterproof. You can set your garden hose on a hard stream and run it from top to bottom for thorough cleaning without ruining the unit.

In fact, an occasional hose down will help the condenser run more efficiently.

As good as water is for your air conditioner, you need to avoid spraying the controls, and the electrical cord attaches to the unit. If you are worried about spoiling your unit, you can always call a professional to help you do it.

How to clean evaporator coils of a window air conditioner

After the filter, cleaning the evaporation coils is essential, but it can be a bit intimidating. The evaporator coils are important for the cooling effect of an air conditioner. They provide the cooling required to produce the cold air that keeps the room cool during hot weather. So cleaning these coils are, the more efficient the unit works.

There are several ways you can clean the evaporator coils depending on if you’re doing a basic or deep clean. But here is a general way of doing it:

Thing You Need

  • Screwdriver
  • Foaming coil cleaner
  • Fin brush
  • Garden hose
  • Coil brush


  • Confirm with the product diagram in your user manual to locate the coils and know how to remove the front panel and filter. Typically to access the evaporation coils, open the front panel using a screwdriver and then remove the filter. The coils are usually at the back of the air conditioner unit behind the filters.
  • Inspect the coils for any dust, cobwebs, and dirt, and dust them off using a coil brush. It is best to brush parallel to the fins to prevent bending them.
  • Use a fin brush to straighten any bent fins to increase the surface area and improve the unit’s performance.
  • Hose down with a garden hose to rinse out the loose dirt.
  • Spray the foaming cleanser on all sides of the coil and let it soak for about 5-10 minutes. The coil cleaner will loosen the remaining dust and grime in between the fins.
  • Then rinse the foaming cleanser with the garden hose. You can also use a rinse-free coil cleanser.


Following the steps explained in the article, you will realize the effects of cleaning your window air conditioner once you use it. The air coming out will be fresher and colder, and if you maintain the regular cleaning, your air conditioner will last through its expected lifespan.