How To Clean Your Air Conditioner Filter In 5 Easy Steps

Knowing how to clean your air conditioner filter is a key part of your regular maintenance routine. How you approach this step plays a huge role in determining whether your HVAC systems function properly. In this post, we’ll look at all aspects of cleaning your filter. That includes the steps required as well as how often you actually need to go about doing this.

How To Clean An Air Conditioner Filter: The Basics

First things first, not all air conditioner filters can be cleaned. If your filter has a cardboard frame or contains some written indication of non-serviceability, you’ll need to replace it outright. You can find replacement air filters in most home hardware stores. Make sure you find the right size; bring your old filter along so you can compare.

Why Should You Clean Your Air Conditioner Filter?

Air conditioners circulate air throughout your home. They rely on filters to trap dirt and debris that would otherwise get circulated alongside your fresh air. When a filter is clogged, the air conditioner has to work a lot harder to pump air. This uses more electricity and reduces your air conditioner’s lifespan (here’s how long your AC lasts in Arizona). Of course, it also reduces your home’s air quality.

How Often Should You Clean Your Air Conditioner Filter?

Cleaning your air filter shouldn’t be something you do only twice a year when you have a professional look at your air conditioner (read more about why we recommend services twice annually here).

You should take care of your filter (whether that means replacing or simply cleaning it) on at least a monthly basis. You might do this much more frequently than that if you live in an area with high pollution or have a dusty hobby like woodworking.

Let your eyes be the judge. If you notice lots of dust built up on your filter during your monthly inspections, consider increasing your cleaning and replacement frequency to every couple of weeks.

How To Clean A Central Air Conditioner Filter

Let’s begin by walking through the steps for cleaning your central air conditioner’s filter. Then, we’ll look at window and ducted units. Keep in mind that these steps only apply if your air conditioner’s filter is reusable. If you have a disposable filter, you’ll have to replace it in lieu of cleaning.

Step One: Determine The Air Conditioner Filter Location

With central air conditioners, the filter typically resides near the cold air return. Throughout much of the United States, this component lies within the basement. With air conditioners in Phoenix, however, it will typically be in the garage or some other type of storage room since houses generally don’t have basements here.

You may also have filters behind your return vents, which will be scattered throughout the house.

Step Two: Shut The Power Off

Whenever you perform any type of servicing on your air conditioner, it’s a good idea to turn the unit off. This will protect it and you.

Step Three: Remove The Filter And Vacuum It

Typically, there will be a good amount of dust caked onto the filter. You can remove most of it using a vacuum with a bristled attachment. Do this for all of your central AC’s filters, including those hiding behind the returns. They’re just as important! Make sure you vacuum either side of your filter.

Step Four: Soak The Filter In A 50/50 Mixture Of Water And Vinegar

Important: Read your filter’s manual (or the instructions printed directly onto it, if applicable) before you do this. Some air conditioner filters aren’t designed to get wet and you definitely want to avoid causing damage.

If your filter is water-friendly, soak it in a mixture of equal parts water and vinegar for about an hour. Before reinstalling the filter, let it dry completely.

If you don’t have a basin large enough to hold your air conditioner filter, use a hose instead. Make sure you set the pressure very low as anything too intense will easily rip through the filter.

Step Five: Reinstall The Filter

Once you’ve cleaned the filter (meaning no dust or debris remains), reinstall it. Most filters have an arrow indicating which way they’re supposed to face. This arrow needs to point in the direction of the airflow.

Congrats! You’re all done. While you’re in a cleaning mood, however, check out this post for some tips.

How To Clean A Ducted Air Conditioner Filter

Now that you know how to clean a central air conditioner filter, let’s look at ducted units. 

Step One: Locate The Air Conditioner Filter Location

With a ducted unit, your filter will be located behind the main return air duct.

Step Two: Shut The Power Off

As mentioned previously, shutting your air conditioner off while cleaning its filter can help you avoid damage.

Step Three: Vacuum And Soak Your Filter Down

Follow the same steps we discussed in the section on cleaning central air conditioning filters. That includes leaving the filter to dry thoroughly before you reinstall it. While all reusable filters will be vacuum-friendly, double-check whether yours is waterproof.

Step Four: Reinstall The Filter And Turn Your AC Back On

Voila! You’re good to go.

How To Clean A Window Air Conditioner Filter

Cleaning your window air conditioner filter doesn’t require anything radically different than with other types of systems. However, it’s a good idea to check for the presence of mold or mildew on your filter when you clean it. Either of these substances would indicate a need for more thorough cleaning.

Step One: Shut The Air Conditioner Off And Unplug It

This is an especially important step for window air conditioners since you’ll be working in close proximity to the air conditioner’s moving parts, whereas the previously-discussed types of units are fairly distant from where the filter is.

Step Two: Remove The Air Conditioner’s Front Panel To Access The Filter

This panel will be held in place by screws, pressure, or some simple plastic clips. Once you remove the panel, it’ll be impossible to miss the filter.

Step Three: Vacuum And Wash Your Window Air Conditioner Filter

As always, read your air conditioner’s instruction manual to make sure water won’t harm the filter. If the filter smells a little musty, that may be an indication of moisture problems inside that would require a more thorough cleaning of the entire unit.

Step Four: Let The Filter Dry Before Replacing It

Return the filter and front panel to their proper places. After that, you’re good to go!

How To Clean Your Air Conditioner Filter: Conclusion

Cleaning your air conditioner filter is not complicated at all. However, it’s easy to adopt a policy of “outta sight, outta mind” here since you probably won’t notice the immediate effects of a dirty filter. It’s important that you make a habit of cleaning the filter, however. Dirty filters make your system run inefficiently and jeopardize your health. Also, check out our guide on window AC insulation for more window air conditioner tips.

For more air conditioning and water filtration blogs, check out these articles on “Different Types of Hot Water Tanks” and “How to Remove Nitrates from Well Water“.

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