How to Clean an Air Conditioner Filter in 4 Easy Steps

With just a little regular maintenance, you'll have clean conditioned air all year round.

By Tony Carrick and Amy Lynch and Bob Vila | Updated Dec 8, 2021 11:29 AM

how to clean air conditioner filter.

Photo: istockphoto.com

Though often overlooked, air conditioner filters are responsible for a mighty important job: keeping dust, dirt, and other debris out of the air we breathe indoors. As they improve your air quality, they also get clogged with all of that aforementioned gunk, which makes cleaning them throughout the year vital for the sake of your health—and your wallet. When a filter is dirty, it forces the air conditioner to work harder in order to push air through its clogged fibers, using more energy to do so and thereby shortening its lifespan. Avoid high utility bills and mechanical problems down the road by keeping the air conditioner filter clean. Removing a washable-type air conditioning filter once a month (or twice during seasons of high use) and assessing it for either cleaning or replacement should keep quality and energy use in check. This guide will discuss how to clean an AC filter and the benefits of performing this routine HVAC maintenance.

Maintaining these filters is easy. Continue reading to learn how to clean an air conditioner filter.

Tools & Materials
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.

STEP 1 : Turn the air conditioning unit off.

Examine the condition of the AC filter to see if it needs cleaning. Before checking over the filter, first make sure your system is turned off—you don’t want unfiltered air circulating throughout your home while the filter is removed. (While you’re looking at the inside of your air conditioner, you might also want to determine whether you need to clean the air conditioner itself, too.)

When it’s safe to continue, unscrew the vent cover or use the release handle to remove the filter. Gently slide the AC filter out, being careful not to damage it, and then give it a thorough look over.

The filter’s exact location will depend on your HVAC system. Most units house their air conditioner filters just behind the return vent, typically found either near the ceiling or close to the floor. Some systems may have multiple return vents (particularly in very large homes), so check around to make sure you’re not overlooking any filters during this maintenance.

When in doubt, call your manufacturer and ask where the AC filter can be found and if your system uses more than one.

RELATED: Best Air Conditioner Brands for Climate Control in 2021

STEP 2: Clean dust and dirt from the filter.

how to clean air conditioner filter

Photo: istockphoto.com

If you can see any grayness, discoloration, or visible surface dust on the AC filter, it’s time to clean the filter—or replace it.

  • Remove the dust and dirt from a reusable air conditioner filter (one with a plastic or metal frame) with a handheld vacuum cleaner or with an attachment at the end of an upright vacuum’s hose. For an even deeper clean, you can use your bathtub faucet or handheld shower head to run warm water through the filter in the opposite direction of airflow. To do this, check to see where the dust is most visible, and then face that side downward; the water should hit the opposite side and pass through in order to rinse out the gunk without pushing it deeper into the filter.
  • If your AC unit uses disposable filters (which are often framed in cardboard), simply replace the dirty disposable filter with a clean one from your local hardware store. Check the size, which is marked on the filter’s side, to avoid buying one that doesn’t fit. Then skip to Step 4.

STEP 3: Allow the air conditioner filter to dry.

After washing your reusable AC filter, let it dry thoroughly. Consult the manufacturer’s instructions for any special steps you might need to take, but, generally, leaning it against the side of the bathtub for a few hours and flipping it over midway should do the trick. You can use a hair dryer set to “cool” to speed things up, but beware that hot temperatures can burn or otherwise damage the filter.

STEP 4: Install the clean AC filter.

Reinsert either a clean, dry reusable filter or a new disposable into your AC unit. Just like the removal process, this part is easy: Simply slide the filter back into its designated slot, making sure the arrows on its frame point away from you and toward the unit.

To keep your airflow fresh from now on, set up a monthly reminder to check the AC filter’s condition. If needed, cleanse or replace the filter in your air conditioner unit at this time. If you live in a warm climates you should check the filter more frequently in the summer; homeowners in cold climates may need more maintenance in the winter. Once you’ve figured out the needs of your particular unit, devise a maintenance schedule and to stick to it so you can breathe easy throughout the year.

RELATED: Choosing an HVAC System

Common Types of Air Conditioner Filters

how to clean air conditioner filter

Photo: istockphoto.com

When selecting an air conditioner filter, choose between disposable and washable options. Ahead, learn about the advantages (and disadvantages) of each type of filter.

Disposable

Disposable air conditioner filters are the most common variety. A disposable filter lasts for about three months, after which you need to replace it with a new filter. Disposable filters are easy to trade out, with minimal tools required. Simply open the air filter cover, remove the old filter, plop in the new one, and close the cover. The downside of these filters is that they present a recurring cost, which can get expensive depending on how many returns are in your home and how premium a filter you use.

Washable

Permanent air conditioner filters use a filter media that is washable. Since they typically last about five years, they’re more economical than disposable filters and, since there is less waste, easier on the environment. The maintenance for a permanent filter is more labor intensive: You remove the filter from the unit, then manually clean and dry it before replacing it back into the return. Most homeowners should repeat this process every couple of months.

The Advantages of a Clean AC Filter

There are several good reasons to clean the filter on your air conditioning unit regularly. First and foremost, the filter protects the air conditioning unit by filtering out dirt and dust that would otherwise clog the air handler and force your AC unit to work harder to cool the air. This strain can shorten the life of an AC unit. What’s more, an AC unit that’s working harder because of a clogged filter will use more electricity, causing your utility bill to skyrocket. Since an air filter removes allergens, dust and other contaminants, it improves air quality in your home, providing relief for allergy sufferers while generally making the air easier to breathe. A clean AC filter can also help to keep the ductwork in your home clean by catching dust and debris that might otherwise accumulate inside of it. To recap, using an air conditioner filter:

  • Extends the life of your air conditioning unit.
  • Makes your HVAC system more energy efficient.
  • Improves the air quality in your home.
  • Keeps your ductwork clean.

RELATED: 16 Must-Have Home Products for People with Allergies

Final Thoughts

how to clean air conditioner filter

Photo: istockphoto.com

While filters for air conditioners may be located behind an inconspicuous grate on a wall or ceiling, out of sight and out of mind, forgetting to change a filter regularly is a big mistake that can cost you money while negatively impacting the air quality in your home. A clogged AC filter can shorten the life of your expensive AC unit while allowing pollen and dust to circulate throughout your home. Whether you choose a disposable or reusable air filter, changing the filter is vital regular maintenance for your air conditioning unit.

FAQs About How to Clean Filters for Air Conditioners

After learning about the processes and benefits of cleaning your air conditioner’s filters you may still have questions. Read on for more information about proper filter maintenance.

Q: How often should you clean an air conditioner filter?

Clean or replace your air conditioning filter once every month or two during the cooling season. If your air conditioner doubles as a heat pump, you should clean or replace the filter once every three months year round.

Q: What happens if you don’t clean the air conditioner filter?

The air conditioner filter will eventually become filled with the dust and dirt it collects from the air, inhibiting air flow through the filter to the air handler. The clogged filter will force the air conditioner to work harder to cool the air in the home, putting a strain on the AC unit while increasing your utility bill. In extreme cases, the poor airflow can cause the cold air to become trapped on the AC coils, freezing them up and rendering the AC unit inoperable.

Q: Does cleaning the AC filter make it colder?

In a sense, yes. A clogged AC filter can trap cold air inside the air conditioning unit, preventing it from circulating through the ductwork and into the home. Replacing the filter improves that air flow, thereby allowing colder air to make its way inside.

Q: Is it safe to run AC without a filter?

While it’s okay to run an air conditioner for a short time without a filter, running one for hours with no filter will eventually cause serious damage to the AC unit while lowering the air quality in your home.