How to Clean an AC Filter

Keep your home’s air clean, allow your air conditioning unit to run more efficiently, and help your filters last longer with these simple tips.

April 08, 2021

Air conditioning units don’t require a lot of maintenance, but it's important to clean or replace your unit’s air filters regularly to reduce the likelihood of airborne mold and common allergens through forced air systems. There are different types of air filters available, and though many are disposable and can’t be cleaned, thanks to changes in technology and related efficiencies, washable air filters are more common than ever. If you’ve previously used disposable filters, this might even be the perfect time to upgrade.

A dusty air conditioner filter from an AC wall unit held up against the sky.

Air Conditioner Washable Filter

How to clean a dusty air filter to improve air quality.

Why Should You Clean Your Air Filter?

  • Cleaner air quality: fewer allergens and less dust.
  • Better unit efficiency, which results in lower energy costs: Dirty filters make the system work harder. The harder it works, the less efficient it is. The less efficient it is, the more it costs to operate.
  • To prolong life of your HVAC unit: This is tied to efficiency. The harder the system works, the faster it can be damaged or overheat.
Vacuuming a dusty air conditioner filter from an AC unit.

Vacuuming an Air Conditioner Filter

How to clean a dusty air filter to improve air quality.

Types of Filters

Disposable Filters

These are usually made of paper or cardboard and cannot be cleaned; they should be thrown away and replaced. You may buy these in bulk to make it easier to replace several times a year, but if you’re running low on replacements and are considering alternatives, this may be the time to invest in washable filters.

Washable/Reusable/Permanent Filters aka Electrostatic Filters

These are considered permanent since they can be cleaned and reused for years; some electrostatic filters are designed to last the life of the HVAC system with proper care. Reusable filters are more expensive up front but can save you money in the long run. They’re typically less effective at capturing small particles than disposable filters, so they may not be the best choice if you or anyone in your household has allergies.

  • Most use air friction to create electrostatic cling to trap particles. You’ve experienced “static cling,” and this is no different.
  • If you’re replacing a disposable filter with a reusable filter, make sure to get the highest MERV filter rating (Minimum Efficiency Reporting Value) your system allows.

It’s always a good idea to save the packaging when you replace your filter, because knowing exactly what type of product you purchased is the first step to knowing if and how it can be cleaned. You should also make it a habit of marking on your calendar when it needs to be cleaned or replaced so you can remember easily.

Once you know what type of filter you have and understand its expected lifespan, you can get to cleaning.

Using a hose to clean a dirty air conditioner filter.

Air Conditioner Washable Filter

How to clean a reusable air filter to improve air quality.

How to Clean Your Air Filter

Step 1: Turn Off Your AC Unit

Keeping the unit off ensures that you’re not letting dirty air circulate through your home while the filter is being cleaned.

Step 2: Remove the Filter

Some units can have multiple filters, so be sure you check all vents.

Step 3: Vacuum the Filter

To reduce the amount of dusty buildup, the first thing you can do is use a hand vacuum to lift allergens. Use the microfiber cloth to clean any dust along the frame. Getting this top layer of sediment and anything loose makes the next step clean and easy.

Step 4: Wash the Filter

In a deep sink or outdoors with your hose, rinse the filter gently and thoroughly, and allow it to dry. If you need to provide a deep clean, soak the filter in a flat bin with 1 part white vinegar and 1 part warm water for an hour, and then rinse it gently with the hose.

Never use a pressurized cleaner on an air filter; they’re simply too delicate for any high-pressure hose.

Step 5: Reinstall the Filter

Check the dry filter for any signs of damage – holes, dirt that could not be cleaned thoroughly or rips in the material. If it's in good condition, you can put it back in the unit. Refer to any expiration dates on the product or its original packaging to make a note of when it needs to be fully replaced.

A dusty air conditioner filter from an AC wall unit.

Air Conditioner Washable Filter

How to clean a dusty air filter to improve air quality.

Other “Filters” on Your AC Unit That You Can Clean

The fins of a window AC unit can be vacuumed or wiped down with a microfiber cloth to remove dust and debris for greater efficiency. Be careful not to bend or squish the fins together. The fins are how the A/C unit “conditions” the air.

  • Unplug the unit.
  • Vacuum or gently brush in the same direction as the fins.
  • Use a butter knife to gently straighten bent fins if necessary.

The exterior of an outdoor central AC unit can be cleaned as well.

  • Remove large debris by hand (leaves, grass clippings or anything else that has been collected by the unit).
  • Use a hose to wash smaller debris off of the unit.
  • Use a butter knife to gently straighten bent fins if necessary.

More HVAC Tips

How to Keep Your Air-Conditioning Unit Running Smoothly

Regular cleaning and maintenance will save you money and extend the life of your heat pump or HVAC unit.

Air Duct Cleaning 101

Learn what you can do to maintain your home's air ducts yourself and when you should consult a professional for cleaning.

Is Ductless Heating and Cooling Right for You?

Considering going duct-free to heat or cool your space? Get the lowdown on when these systems are the right choice and what to expect when you install.

Next Up

Why I Decided Not to Get Central AC

Get the pros and cons of ductless cooling and heating. Is it right for you?

How to Clean AC Coils

The summer heat is hard on an air conditioning system. This year, stop the problems before they start by cleaning your coils and taking other small precautions to set your system up for success and lower your utility bills.

5 Best Portable Air Conditioners Under $525

Beat the summer heat with a portable AC unit. Check out these top-rated models with features like quiet operation for bedrooms and dehumidifiers for hot, humid spaces.

Should I Cover My A/C Unit in the Winter?

Learn the right and wrong way to protect your A/C unit during the off-season.

Air Duct Cleaning 101

Is cleaning your HVAC air ducts really that important? Get to know your home’s system, learn how you can improve its function yourself and know when it’s time to consult a professional for cleaning.

How to Recharge Your Car's A/C in 15 Minutes

Get your car's air conditioning in shape for summer and beat the heat with these easy steps.

Easy Steps to Keep Your Air-Conditioning Unit Running Smoothly

Regular cleaning and maintenance will save you money and extend the life of your heat pump or HVAC unit.

How Ductless Air Conditioners Work

Thinking of installing a new ductless HVAC unit or switching out your existing system? Get the 411 on all the pros, cons and details to discover if it's the right choice for you.

Swamp-Cooler Maintenance

Check out these cleaning tips for energy-efficient evaporative coolers.

The Best Deals on Window-Mounted and Portable Air Conditioners Right Now

Find the right fit for your space, and stay cool this summer without breaking the bank.

Go Shopping

Refresh your home with stylish products handpicked by HGTV editors.


Home Town

1pm | 12c

Home Town

2pm | 1c

Home Town

3pm | 2c

Home Town

4pm | 3c

Home Town

5pm | 4c

Home Town

6pm | 5c

Home Town

7pm | 6c
On Tonight
On Tonight

Home Town

8pm | 7c

Home Town

9pm | 8c

Home Town

10pm | 9c

Home Town

11pm | 10c

Home Town

12am | 11c

Home Town

1am | 12c

Home Town

2am | 1c

Home Town

3am | 2c

Home Town

4am | 3c

Home Town

5am | 4c

Follow Us Everywhere

Join the party! Don't miss HGTV in your favorite social media feeds.

Related Pages