Getting Fresh Air – How to Clean an AC Filter

As an Amazon Associate we earn from qualifying purchases.

​Some people might wonder how an air conditioning system works in maintaining a comfortable temperature for an enclosed space. Many may even believe that air conditioners take in fresh air from outside and bring it indoors, but the truth is, it doesn’t work the way we assume.

How an Air Conditioner Works

Your air conditioner works by taking the hot air and blowing the cold air back into the same room. Your cooling system (keeps your home or office at an optimal temperature) typically works the same way as your refrigerator (cools a tiny insulated space).

If you take a few minutes to inspect your air conditioning system, you’ll find an indoor and outdoor unit connected to each other. Most air conditioning units capture the hot air and process it with the help of components like filters, compressor, evaporator coils, condenser, and expansion valve (regulates refrigerant flow), to release fresh cool air inside your home.

Air conditioner close up

However, things like dust, mold, pet dander, airborne bacteria and allergens may cause serious health problems to you and your family by polluting indoor air. Modern day air conditioners are equipped with HEPA filters (designed to trap dust and microbes) which are attached to the indoor unit, making it easier to clean them.

Air Conditioning Filtration

The filter is a crucial component of your air conditioner that stops recirculating the contaminated air inside your home. So, to improve the overall indoor air quality, it is essential to keep the filters clean or change them regularly when your unit is not functioning correctly.

Filters need more frequent attention when your air conditioner is in constant use. If you fail to maintain them regularly, your filters may get clogged, which diminishes the performance of your unit – not good for you or your air conditioner.

If your system works harder and longer than it should then there could be a problem (a blockage in the unit’s airflow) with your filter, so, you must clean your filters regularly to keep your air conditioner in good shape and enhance the quality of the air you breathe indoors.

In doing so, you can improve your unit’s efficiency and also lower the future maintenance costs – helps to keep your living space comfortable, the surrounding air clean, and your wallet full of money. So, it is essential to clean the filter of your air conditioner at least once every three months.

Why You Should Keep Filters Clean

As a homeowner, it is your responsibility to keep your home free from dust, bacteria and other contaminants that can make you and your family members sick. The filters in your air conditioner can do wonders in trapping these harmful elements, but only if they’re kept clean.

It is essential to clean or replace your filters regularly to ensure that your unit provides fresh air throughout the day. So, you must clean or replace them regularly to provide clean, cool air during the hot summer days. It also helps to keep your utility bills as low as possible and helps your unit operate at its peak efficiency.

If you frequently replace your air filters and still notice that your unit is not performing to the best of its ability, then go with an air conditioning service expert who can help you to find and fix problems immediately.

Close up of an ac filter

How to Clean an AC Filter

Examine the performance of your air conditioner and the quality of air inside your home, to see if your filter needs cleaning. The following are a few tips to follow if you consider cleaning the filters on your own:

  • Step 1: Before initiating the cleaning process, turn off the power to your unit and unplug the cord from the electric socket. Make sure that your air conditioner has been cleaned prior and is completely shut down, to avoid being electrocuted while the filter is removed.
  • Step 2: When it’s safe to continue, you can unscrew the front panel and use the release handle to take out the filter. The placement of your filter depends on the type of air conditioning system you own, so do it accordingly. In most cases, the filters are located closer to the vent.
  • Step 3: While removing make sure that you don’t accidentally damage the filter, so be very careful. Give it a thorough look to check whether there are any deposits (visible stains) or dust on the surface layer of your filter.

​​​If it is a reusable filter, you can either wipe off the dust particles using a soft cloth or clean its surface with a low suction vacuum cleaner. In case of any damages, it is better to replace your filter with a new one, helping your system to work more efficiently.

Suppose, if your AC unit is equipped with a disposable filter, replace it with a brand new one from the local hardware store. Always check the size, to avoid buying the one that doesn’t fit your unit.

  • Step 4: If your filter still looks dirty, wash off with a mild stain remover and rinse it with clean water – do not put it in the dishwasher. After washing your reusable AC filter, let it dry thoroughly before reinstalling it back to the unit. Just like how you removed the filter, simply slide it back to the designated slot.

Other Clean Air Tips

Leave enough space around the outdoor unit and make sure that no bushes or plants are interfering with the air flowing through it. Also, clean the surroundings regularly to get rid of the dust accumulated over time.

The coils are one of the most critical parts of your air conditioning system. You must ensure to clean them at regular intervals or else it could possibly lead to the break down of the unit.

An airconditioning unit outdoors

Ensure that the gutters above your outdoor unit is protected with guards to prevent water leaks.


Lack of maintenance can take a heavy toll on your unit’s efficiency. So, schedule an appointment for annual maintenance of your air conditioner by hiring a local technician – an expert would test the thermostat, check the refrigerant levels, and ensure that all the components of your unit are kept in good condition.

Allen Michael is the Founder and Editor of Home Viable, a website that he started to provide readers with tips on home efficiency and automation. He draws on his engineering background combined with his family-of-four experiences for his articles.