You are in Georgia. Visit Alabama. Visit Tennessee.

You are in Georgia. Visit Alabama. Visit Tennessee.

You are in Georgia. Visit Alabama. Visit Tennessee.

You are in Tennessee. Visit Georgia. Visit Alabama.

You are in Tennessee. Visit Georgia. Visit Alabama.

You are in Tennessee. Visit Georgia. Visit Alabama.

You are in Alabama. Visit Georgia. Visit Tennessee.

You are in Alabama. Visit Georgia. Visit Tennessee.

You are in Alabama. Visit Georgia. Visit Tennessee.

Step by Step Guide to Changing Air Filters


The effectiveness and efficiency of the AC portion of your HVAC system partially depends on a working filter. Changing an air conditioner filter is a simple job, and it’s one that every homeowner should know how to do themselves. To help with this, we’ve broken down this task into an easy how-to guide.

Types of Disposable Air Conditioner Filters

#1. Mechanical

The two types of mechanical HVAC filters are charcoal and fiberglass. Fiberglass filters come in one and two-inch thicknesses. These are the cheapest and least effective filters. They also need to be changed more often than any other type. During the times when you’re using your HVAC unit frequently, you should plan to replace a mechanical filter at least once a month.

#2. Pleated Filters

Pleated filters can trap between 35 and 40 percent of indoor air pollutants. Their effectiveness is directly related to the amount of fiber there is per square inch. The more fibers there are, the more particles the filter can trap. Pleated filters should be changed at least once every 45 days.

#3. High-Efficiency Pleated Filters

4”-5” pleated filters require a separate cabinet installed between the furnace and return plenum box. These are very common filters that filter over 90% of the dust that goes thru the filter. They are extremely efficient filters that usually only require replacement about once a year, depending on how often your system runs.

#4. Electronic or Electrostatic

Electrostatic air conditioning filters are the most expensive and most effective type of filter. They rely on electricity to trap small particles that other filters can’t attract. These filters need to be changed/cleaned every three months.

Changing a Disposable Air Conditioner Filter

If you are a new homeowner and this is the first time you need to change your air conditioner filter, either locate the copy of your system’s service manual or find it online. This way, you’ll know what size and type of replacement filter you need to have.

Once you know what type of replacement filter you need, then you’re ready to start changing the filter!

Step One: Before you do anything, make sure that your HVAC system is turned off.

Step Two: Next, you’ll need to find the filter. Air conditioning filters are typically located in one of two places. If you have an oversized return-air register on the wall, the filter may be located under the grille. If your HVAC system is located in a utility closet, the filter is probably located in the air-handler cabinet. Upflow/horizontal systems located in basements or attics will usually have a small 1” filter rack with a removable door located outside the furnace between the furnace wall and return plenum box.

Step Three: Regardless of whether the filter is in a cabinet or behind a grille, you may have to remove the screws to get to it. An external filter rack will usually have a metal door with a handle that will just simply pull off. Be sure you put the screws in a visible location where you can find them later once it’s time to put them back on.

Once you remove the cover over the filter, you should clean it before you change the filter: For a grille cover, you should use an attachment to vacuum up dust clumps. Wash the cover thoroughly, so every slot is free of debris.

To clean a cabinet cover, wipe the outside down with a soapy rag. For the inside, there may be a substantial dust buildup. Use a vacuum cleaner attachment to get into crevices.

Step Four: Remove the dirty filter and place it in a trash bag to prevent any filth from scattering throughout your house. If it’s a washable filter, take it outside and gently wash it off with a garden hose and allow to dry before reinstalling.

Step Five: Before you replace the filter, check for the arrow that indicates which side is up, this arrow will usually point towards the furnace. Most disposable filters have a designated place where you write the date on which you’re putting a clean filter in or the date on which you need to replace the filter.

Once you’ve written the date down, slide the clean filter into place and replace the register grille or air-handler cover.

Keeping your air conditioner filters in tip-top shape is just one way to extend the life of your system and ensuring optimal performance and efficiency. With a Coolray Coolcare Heating and Cooling Maintenance Agreement, you’ll never have to worry about general maintenance or expensive repairs. Our experts will visit your house and your system and perform seasonal checks, including looking out for your air filters.

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