How to Clean an Air Conditioner Filter in 6 Easy Steps

By Marilyn Syarto


If you are looking to save money on your energy bill while keeping cool indoors, why not learn how to clean an air conditioner filter the right way? And that’s only one good reason why you should clean your air conditioning unit’s filter.


An air conditioner filter plays an important role: It’s the barrier that keeps allergens and bacteria from entering your home through the machine. The filter can get pretty nasty over time, and letting grime build up can lead to all sorts of issues. Here’s how to clean your air conditioner filter step by step, plus when to know it’s time for a cleaning.

outdoor air conditioner next to a brick wall and a garden with a pink blooming flower

Photo via Easy Air & Heat


Why You Need to Clean Your Air Conditioner Filter

There are a few important reasons why your air conditioner filter needs cleaning:

  • As we mentioned above, a clogged air conditioner filter can make itself known on your energy bill. Replacing or cleaning a dirty, clogged AC filter with a clean one can lower your unit’s energy consumption by up to 15 percent, according to Energy.gov. The savings can add up if you use multiple window or wall units throughout your home.
  • Cleaning it means you’ll breathe in clean air minus the microbes, allergens, dust, dirt, and other particles the filter is meant to snag.
  • Cleaning your filter will help your unit run efficiently. An inefficient AC unit will run wonky and can freeze its inner coils and restrict cool airflow, according to Coastal Heating and Air Conditioning.
  • Cleaning your filter will extend the life of the machine.


When to Clean Your Air Conditioner Filter

As soon as warm weather hits, open up your AC or pull out the filter (the filter location depends on your specific unit) to check on the filter’s condition. If you see even a thin layer of dust on your filter, you should clean it. (You can even take it a step further and deep clean your AC without having to call in the pros.)

The following can have effects on your air conditioner filter:

  1. Pets: If you have pets in your home, it helps to check your AC filter’s condition every few weeks to see if there’s any pet hair buildup you can wipe out.
  2. Construction: If there was any sort of construction in your home or nearby, check the filter frequently for a thin layer of dust buildup that can be removed.
  3. Dryness: If you live in a dry, dusty area or you’ve experienced a windstorm or wildfires, you need to frequently check and clean your AC unit’s filters.
disposable air conditioner filter with diamond-shaped structure

Photo via D.I.Yankowski


Types of Air Conditioner Filters

Not every filter can be cleaned. There are also AC filters that are disposable and replaceable. In addition, your model may have more than one filter that needs cleaning. Your best bet is to check your owner’s manual or look for it online by the brand and model number. Regardless of what type of AC unit you have (central, room, portable, or ductless mini splits), there will be a filter you’ll need to tend to that could be one of the following:

  • Disposable filter: Made from paper with a cardboard frame, this type of filter cannot be cleaned and needs to be replaced several times a year, so buy it in bulk. Disposable filters are known to be better at catching smaller particles.
  • Permanent electrostatic filter: This is the type of filter you pop or slide out for washing. It’s reusable and should last for years. These filters work almost like “static cling”—using friction to trap particles in the filter. These filters cannot capture as many small particles as disposable filters can.


What Is a MERV AC Filter?

Look for an AC filter with a high MERV rating (minimum efficiency reporting value). The higher the MERV number, the more contaminants the filter can remove. A filter with a MERV rating between 13 and 16 is ideal, removing up to 75 percent of airborne particles from the air, according to General Heating and Air Conditioning. With that being said, always consult your owner’s manual for the recommended filter.

yellow rubber-gloved hand steadies an air conditioner filter being vacuumed with brush attachment

Photo via Shutterstock


How to Clean Your Air Conditioner Filter

If you are able to clean your filter and you know where it is, half the battle is over. The following steps to clean your AC filter refer only to permanent electrostatic filters, not the disposable ones that need to be replaced.


Tools and Materials Needed:

  • Screwdriver (if the filter is screwed in)
  • Vacuum and brush attachment
  • Sink, bathtub, or plastic bin
  • White distilled vinegar or mild liquid dish detergent
  • Water
  • Microfiber cloths
  • Garden hose (optional)
  • Soft towels
  • Hairdryer (optional)


Step 1: Turn Your Unit Off

It’s safe enough to turn your air conditioning unit off and unplug it. You don’t need to cut the circuit to the AC to clean the filter.


Step 2: Remove the Filter

Gently remove your filter by sliding it out, opening the front panel to pop it out, or unscrewing it. There may be clips or screws that need to be removed to access the filter. Some models require you to simply slide the filter out like a dryer’s lint trap. As we mentioned, it all depends on your model. If you do have to remove hardware, store it in a safe spot so it doesn’t get lost.


Step 3: Vacuum the Filter

Grab loose dust, dirt, and other particles with the brush attachment of your vacuum. Vacuum both sides of the filter.


Step 4: Wash the Filter

If there’s still dirt and grime on the filter after your vacuum job, the filter is likely in need of a deep clean. Fill a sink or deep plastic bin with one part water and one part white vinegar or a few drops of liquid dish detergent. Mix the solution with your hands and lay the filter in it to soak for an hour.


If the filter is not terribly dirty, bypass the soaking stage and simply wipe down the filter with the solution.


Skip the Pressure

Never use pressurized air or a pressure washer on an AC screen. The screen is too delicate for the force.


Step 5: Rinse the Filter

Gently rinse both sides of the filter with clean water or a gentle stream from a garden hose (if you’re cleaning outdoors).


Step 6: Dry the Filter

Gently dry both sides of the filter with a soft, dry towel, use a hairdryer on a cool setting, or air-dry thoroughly before reinstalling the filter to avoid any mold issues. When reinstalling, make sure the filter is pointing in the right direction (there are usually arrows indicating which side of the filter should be inserted).

window air conditioning unit on a blue house

Tips for Keeping Your Air Conditioner Clean

You’ve cleaned your air conditioner’s filter, but the job’s not over yet. There are a few steps you can take to keep your machine’s filter cleaner for longer:

  • It probably goes without saying, but you should never run an AC without a filter, or else dirt, debris, and dust will build up on internal components and can ruin your appliance.
  • Frequently open the filter to wipe it down on both sides with a dry or barely dampened (with water) soft microfiber cloth to catch particles.
  • Don’t just clean the filters—clean the fins, too. Unplug the unit and gently wipe them down with a dry microfiber cloth or vacuum with the brush attachment to remove dust and debris. Use light pressure when working on the fins so you don’t bend them.
  • Remove leaves and other debris from the outside of the unit that could be blocking airflow. This doesn’t mean you can’t make the exterior of your AC look more inviting, but just make sure there’s plenty of room for it to breathe.


Have you rejuvenated a gross AC filter? What did you use to clean it? Please share your tips with the community!

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