How To Replace An Air Conditioner Filter

By Editorial Team

Updated on April 19, 2024

An air conditioner is an important unit in any home, keeping things cool and comfortable throughout those warm summer months. However, if your AC unit happens to break, it’s likely you’ll take serious notice.

To avoid reaching a point of no return with your AC unit, it is important to perform semi-regular maintenance, and one of these jobs includes cleaning the internal parts, especially the air conditioner's filter!

The air conditioner's filter is one of its most important pieces, and cleaning it is the most basic maintenance you can perform. Of course, how to do this will greatly depend on the air conditioning system you have in place. Nonetheless, we will look at a few different ways to clean your air conditioner filter and keep the unit running smoothly. 

Identify the type of filter

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There are a few different filter types, and they will need to be identified if you're going to find a replacement for the one in your home.

Fibreglass

You can tell if the filter is your air conditioner is fibreglass as it will resemble your typical window screen with a much larger frame. This type of filter is considered outdated by many, but should still be easy to find. However, if you have a fibreglass filter, it should be changed at least once a month.

Pleated

A pleated filter is a rectangular filter that is approximately 1-inch wide. It should be replaced every 45-90 days, depending on whether your family members have allergies or if there are pets in the home.

Media

A media filter is very much like a pleated filter, but is much larger and can be around 4 times its size in width. This type of filter will need to be replaced the least frequently, about every 6 to 8 months. In some rare cases, the filter will last up to a year. 

Locate and remove the air filter

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Source: Canva

The first step to changing your air conditioning unit’s filter is finding it in your home, and as we mentioned, this will greatly depend on the unit you’ve got kicking around. Regardless of your home’s air conditioning system, make sure it has been turned off before beginning any work. Some households will have filters which are located behind the main vent that allows for cool air to flow, and this vent will generally be located somewhere close to the thermostat.

If this is the case in your home, you can remove the filter by simply pulling back the fasteners that keep it in place, and swinging it out of the way. You’ll want to remove the old filter immediately, as it will contain many allergens, and therefore, should be placed in the outside trash as soon as possible. Also, when removing the filter from this style of unit, there will be plenty of dust buildup.

Therefore, it is important to have a damp cloth on hand to wipe up any excess that may fall from the ceiling. If your furnace unit is much larger, the filter may be in a slot within the furnace or behind a filter cap. A filter cap is a metal or plastic housing that will easily snap off by hand. Again, once you've located the filter, just remove it.

Make sure that you are certain about whether the filter should be discarded and replaced, or cleaned and returned to its spot in the unit, as you don't want to toss away something you may end up needing.  

Window Air Conditioner Units

Window AC units will differ from other units, and the filter will be found in direct accordance with where the cool air flows out. This style system allows for the filter to be replaced less frequently, about once a year. However, window air filters will need to be regularly cleaned to continue functioning smoothly, and this will greatly depend on how often you are using the air conditioner.

To replace the filter in a window unit, start by turning off the air conditioner first. Next, locate the filter within the unit. Once you’ve found it, remove the filter and take it outside where you should firmly hit it against a flat surface. This will release a good deal of dust that has collected throughout the air conditioner's life. Next, take a damp cloth and wipe down the filter itself, allowing it to dry out completely. Once dry, the filter can be placed back inside your air conditioner.

Finding a replacement filter for your air conditioner

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Source: Canva

If you’ve decided that the air filter in your AC unit is no longer working, or is in bad shape, you’ll need to replace it. The most important thing to determine when looking for a replacement filter is having it the correct size for your home's unit. There should be a label number located on the filter itself, and this will give you the exact measurements of the filter.

If you are unable to locate this, simply take a measuring tape to the side of the unit and measure the air filter's spot. Make sure that before putting in a new filter, that it is installed following the arrows which clearly mark the way the filter should face. Also, be certain that the filter fits correctly, as any escaping air will lead to problems with performance in the future. 

Get 3 renovation quotes for your air conditioner unit renovation project

RenoQuotes.com can help you get quotes for. By submitting your air conditioner unit project to us, we’ll put you in contact with top-rated contractors. Fill in the form on the homepage (it only takes a few minutes), and you will get estimates from trusted professionals.

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