How To Clean A Window AC Unit Without Removing It

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Once you have chosen the right sized window AC for your space, you will need to keep it in good shape, and one of the most important maintenance jobs is keeping it clean. Removing the entire air conditioner can be quite cumbersome, but with the right tools and some patience, you can easily get your unit running at maximum efficiency. Start by unplugging the unit to protect yourself from any possible electrical hazards. You will need a screwdriver to remove the front panel, along with a vacuum with a brush attachment, mild dish soap, microfiber cloths for wiping, and a soft-bristle brush. You will also need a garden hose or spray bottle filled with warm water for rinsing and a foaming coil cleaner specifically designed for AC units, like this Arm & Hammer Foam Spray on Amazon.

Begin by removing the front panel carefully, which is usually held on by two screws at the top or sides. The mesh filter should easily slip out and can be washed in warm, soapy water, then left to air dry. While it dries, use your vacuum brush attachment to suck up loose debris from the front vent and inside surfaces. Do not use a lot of pressure on the metal fins of the coils, they are thin and can easily bend.

With the filter removed and the debris vacuumed, it is time to take on the evaporator coils. Use the spray foam across the coils, making sure to cover it completely. The foam will expand into the crevices, breaking down dirt and mold that basic wiping cannot reach. Let this sit for 10 to 15 minutes, or whatever the product instructions specify. While waiting, you can move onto the outside of your unit to clean the condenser coils. You would use the same foam cleaner on this side, applying it all over.

After the foam has done its job, rinse both coil sets thoroughly. For the inside, use a spray bottle with warm water to avoid making a mess or getting too much liquid into electrical components. Try to angle your spray downward to flush the dirt into the drain pan. Outside, a gentle hose stream will work fine but avoid using a lot of water as the drain pan can only manage so much. Some foams advertise a "no-rinse" option, but this step can help get into the fins, for a better clean overall. If you still see dirt or buildup, you can use a soft brush to get in between and clear out the debris. This Boao Condenser Fin Comb on Amazon is made specifically for this job. Also, spraying a little hydrogen peroxide mix on the inside of your air conditioner at the end can help prevent mold.

Before reassembling, take a second to make sure any of the electrical components or areas near wiring are completely dry. You should also check the drain hole for any clogs; a straightened paperclip would work well to push out anything creating a blockage. Please note, not all units have a drain hole so if you do not see one, do not worry. Reattach the clean filter and front panel, then plug the unit back in. Let it run for about 30 minutes. It should be noticeably cooler.

For ongoing maintenance, make sure you clean the filter monthly during peak seasons, and repeat the foam cleaning process at least once a season. During the winter, when not in use, protect the outside part of the unit with a waterproof cover to minimize dirt and debris. There are also ways to keep your windowed air conditioner from smelling if you start to notice a persistent odor. If there are major problems like heavily reduced airflow or weird noises, shut off your unit and reach out to a professional service that can handle more complex issues.