How to Clean a Window Air Conditioner

Cleaned window air conditioner next to pink flower bouquet

The Spruce / Nanor Zinzalian

Project Overview
  • Working Time: 1 - 2 hrs
  • Total Time: 2 - 3 hrs
  • Skill Level: Beginner
  • Estimated Cost: $5 - $30

Cleaning your window air conditioner offers a surprising slew of advantages. Maintaining a window unit by keeping it clean helps keep it working well by:

  • prolonging its longevity
  • reducing the need for repairs
  • reducing your energy bill
  • preventing mold formation
  • producing cleaner air for your room

Unfortunately, this essential maintenance task is often neglected, leaving your unit vulnerable to premature failure or malfunctioning components. The good news? Cleaning your window air conditioner is quick and easy to do, and it requires a minimal amount of tools and materials. Read on to learn how it's done, and how often you should do it.

How Often to Clean a Window Air Conditioner

The Department of Energy recommends performing a thorough cleaning of your window air conditioner at least once a year, preferably before its first use of the season. In addition to an annual cleaning, the filter should be cleaned once a month and replaced with a new one every three months.

Before You Begin

The moist environment of your air conditioner is an ideal breeding ground for mold growth, which can pose a variety of health risks to you and your household. Hydrogen peroxide has potent anti-fungal properties, making it ideal for eliminating the lingering mold spores air conditioners tend to harbor. Other common anti-fungal cleaners (like bleach) are corrosive to metals and should be avoided to prevent damaging your air conditioner's internal components. Before you clean your unit, fill a spray bottle with a 3 percent hydrogen peroxide solution to use while cleaning.

Next, ensure that the unit is disconnected from electricity by unplugging it from the wall or by shutting off the circuit breaker on your home's electrical panel. This will prevent any risk of electrocution.

What You'll Need

Equipment / Tools

  • Shop vacuum with brush attachment
  • Knife with thin blade or fin comb
  • Cleaning cloth
  • Spray bottle
  • Can of compressed air (optional)
  • Pair of protective gloves
  • Screwdriver

Materials

  • 1 bottle of 3 percent hydrogen peroxide
  • AC coil cleaner (optional)

Instructions

Materials and tools to clean a window air conditioner

The Spruce / Nanor Zinzalian

How to Clean a Window Air Conditioner

  1. Remove and Clean the Face Panel

    The face panel (or grille cover) is a plastic or metal grate secured to the very front of your air conditioner. It will either be secured onto your unit with screws, clips, or tabs, or both. Consult your user manual for specific instructions on how to remove it. The filter may be housed inside the face panel on some models. If so, use the manufacturer's instructions for removing the filter before cleaning the face panel.

    Once the face panel—and possibly the filter—has been removed, spray the panel down with your cleaning solution and clean it off with a cloth. Alternatively, take it outside and spray it down with a garden hose. Set the face panel aside to dry while you clean the rest of the components.

    Air conditioner faceplate pulled out and cleaned with cloth

    The Spruce / Nanor Zinzalian

  2. Remove and Clean the Filter

    Consult your air conditioner's user manual for specific instructions on how to remove the filter. Some units will have the filter housed inside the face panel, while others will have the filter situated directly behind the face panel. Once removed, remove heavy sediment deposits with a vacuum, and wipe it down with a wet cloth to clean residual dust and debris.

    For a deeper clean, take it outside and spray it down with a garden hose. Before reinstalling it, set the filter aside and allow it to dry thoroughly, which should take a couple of hours when flipping it over midway.

    Window air conditioner filter removed and cleaned with vacuum

    The Spruce / Nanor Zinzalian

  3. Vacuum Out the Interior

    Vacuum out the entire interior (or cabinet) of your air conditioner. This includes the drain pan on the bottom of the unit, the fan and blower in the middle, the evaporator in the front, and the condenser in the back.

    Place special emphasis on cleaning the thin, aluminum fins on the evaporator and condenser. If possible, use a soft brush attachment on your vacuum hose and vacuum in the same direction as the fins (vertically, or up-and-down) to avoid bending or damaging the fins.

    Tip

    The aluminum fins on the compressor and evaporator can be sharp, so it's wise to wear protective gloves when handling these parts.

    Vacuum with soft brush attachment cleaning interior of air conditioner

    The Spruce / Nanor Zinzalian

  4. Spray it Down

    Spray down the interior cabinet and exterior housing with hydrogen peroxide, and use a cloth or rag to wipe down everything that you can reach.

    You can use the same spray cleaning solution on the evaporator and condenser coils, or you can use an AC coil spray cleaner. In either case, you can allow the cleaner to air dry or rinse it off with water. If you decide to rinse it off, allow the cleaner to soak for 10 to 20 minutes to let it loosen up any caked-on material.

    Tip

    Before spraying down the condenser and evaporator coils, consider spraying down the fins with a can of compressed air. This will remove any sediment the vacuum may have missed, and provide a deeper clean.

    Air conditioner interior sprayed with cleaning solution

    The Spruce / Nanor Zinzalian

  5. Straighten the Fins

    Bent fins on your evaporator or condenser can reduce your air conditioner's performance or lead to premature failure. Wearing gloves, insert a knife or fin comb in the space between the fins, just above or below the portions that are bent. Gently run the knife or comb in the same direction (parallel with) the surrounding, unaffected fins until the bent ones are straight.

    Knife running between fins to straighten

    The Spruce / Nanor Zinzalian

Tips to Keep a Window Air Conditioner Clean Longer

  • Clean the air filter at least once a month, and replace it every three months.
  • Dust the exterior of the unit weekly and wash with a damp cloth monthly.
  • Remove the unit from the window and store it during the off-season.
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Maintaining Your Air Conditioner. United States Department of Energy.

  2. Could Your Air Conditioner Be Making You Sick? Consumer Reports.