How to Clean a Window Air Conditioner Without Removing it

Written by: Paul Cathro

Updated on: January 30, 2023

window air conditioner unit

A window air conditioner is one of the best ways to remain cool in hot weather, therefore it’s important to know how to keep it in top working order.

Save yourself money on future repairs and replacements by following our guide on how to clean a window air conditioner without removing it.

As with all AC units, you should make sure you book full maintenance of your air conditioner at least once a year.

This will involve checking the state of the coils, removing any dirt, debris, and ice, inspecting the air vents and straightening the coil fins.

You can do some of this yourself, but remember, if in doubt call a professional.

How to Clean Your Window Air Conditioner

Cleaning a window air conditioner might seem like an awkward thing to do, but in a few short steps, you can have it cleaned and working at its efficient best again in no time.

What You Need

The secret to a good job lies in the preparation!

Here's a list of what you'll need to make sure your window AC unit gets a good clean.

  • A vacuum with a small nozzle or soft brush that can be attached
  • A bucket of warm soapy water
  • A soft brush
  • The user manual for your AC
  • An old cloth
  • A spray bottle filled with warm soapy water
  • Gloves to protect your hands from sharp edges
  • An old sheet or newspapers to protect the carpet under where you will be working
  • A screwdriver


  1. 1
    Switch off and unplug your air conditioner to make sure that there is no electricity passing through it while you work.
  2. 2
    The next thing you need to do is remove the front grille, to give you access to the filters and coils within. Often, this can be done by simply pulling the grille down and out, although it may be screwed in, in which case you’ll need a screwdriver for the job.
  3. 3
    Remove the filter. There are two types of filters commonly used in window air conditioners: disposable and reusable. If your filter is disposable and your AC is showing signs of mold or other build-up, it’s time to replace it with a new one. If your filter is reusable, you need to clean it. This can be done with a gentle solution of warm water with detergent or dishwashing soap, applied with a sponge or a soft brush. You can also leave it to soak in a sink of warm water and detergent, as this will help loosen up any grime and make it easier to clean.
  4. 4
    Using a vacuum cleaner, return to your air conditioner and clean away any dust and debris that may have gathered inside the unit.
  5. 5
    Using a mild solution of warm water (with bleach if the dirt is proving hard to remove) and a cloth, wipe the remaining dirt and any visible mold away from the interior of your AC. One of the best ways to tackle mold is by using warm water mixed with a little bleach, as this not only cleans but it kills the mold spores and stops future mold growth in its tracks.
  6. 6
    Once cleaned, you should wipe it dry with a towel or cloth. If you’ve washed a reusable filter, make sure this is propped up to dry too.
  7. 7
    Once your unit and the filter are completely dry, replace the filter, screw the front grille back on and plug back in.

Regularly cleaning your window AC unit is essential to keep it working efficiently and also to ensure that it lasts as long as possible without needing to be replaced.

If you force an air conditioner to work too hard by way of it being clogged up with dirt and grime then you might find its lifespan is significantly reduced.

It’s advisable that you perform a full clean on your window air conditioner at least once a year - an ideal time to do this is in spring or early summer before you will start really needing to use it.

Monthly AC Maintenance Check

An air conditioning unit is likely one of the most expensive appliances in your home so it makes sense to look after it well.

Most AC specialists recommend a quick monthly check-up.

All it takes is a quick clean of the filter, emptying the condensation tray (if applicable), and a brief visual inspection.

If you see or smell mold then you can take action quickly and give your unit a spot clean.

If you notice your AC is taking longer to cool a room or not cooling as well as it once did then take action immediately. Perform a cleaing yourself before calling a specialist if the problem persists.

HomeLabs 6,000 BTU window AC

Air Conditioner Best Practices

In order to get the most out of your window AC unit there are some best practices that you should follow. These tips will ensure that your AC runs efficiently for longer.

  • Schedule regular maintenance checks. It's really important that you keep on top of any filter blockages and any build-up of dirt and mold. In my experience of living in the city, the filter can block quite quickly. A blocked filter really hampers the efficiency of an air conditioner and will cause your electricity bills to skyrocket.
  • Use your air conditioner regularly. Yes, even in the winter! But, why would you use an air conditioner in the winter when it's cold? This used to happen to us every time summer came around each year. We would turn on the AC after 4 months of it being unused and it would just stink due to the mold that had built up inside. The damp, cooler winter air is perfect for mold to creep its way in. By using your AC for just a few minutes every few days you'll prevent mold from being an issue when summer rolls around again.
  • Get it serviced every year or two. AC units will need a refrigerant top-up every couple of years. Refrigerant is the chemical that does the cooling and when it gets low your air conditioner will stop working. It's a really simple job to refill but it should be done by a professional. 
  • Keep it well protected. If possible, install it on a window that is more shaded. Shade means less heat which is great for the lifespan of your window unit. Also, when it's not in use, consider keeping it somewhere cool and dry. That way you can protect it from the harsh winter weather and the early onset of damaging rust.
LG window AC controls

The Importance of Cleaning Your Window AC

Cleaning your window air conditioner isn’t just important for prolonging the life of the unit, but it is vital for protecting the health of your home’s inhabitants.

One of the main problems that can occur with window AC units is that they are vulnerable to mold. A build-up of moisture and lack of airflow can cause mold spores to form, which are then released into your home and living space.

Mold spores can be damaging for your property and for your respiratory health, so it’s important that you reduce the chances of them spreading.

If your window AC starts producing a dank, musty smell when it’s turned on, or you can see mold forming on the exterior, it’s definitely time for a clean.

Cleaning your window air conditioner will not only improve your personal health and that of your property, but it will also ensure your AC will last as long as possible, negating the need for frequent repairs or replacements.

Check back soon for more guides like this!

About the Author Paul Cathro

Paul is an ex-HVAC engineer with 5 years 'in the trade'.

He acquired in 2022 and aims to make it the internet's most comprehensive HVAC resource for small homes in the next few years.

You can learn more about Paul's story here.

Browse his published work on the website here.

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