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Air Conditioner (A/C) Filters Profile:

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When to Replace Your A/C Filter

Changing your air conditioner filter every 1-3 months will not only help improve your indoor air quality in your home or business, but it will also keep your HVAC system clean, reduce energy costs, and prevent costly repairs.

If you are looking for a filter for your window air conditioner you can find what you need here (link to window air conditioning unit cat page when ready).

What Size A/C Filter Do You Need?

When it comes to air conditioner filters, size is most important. A/C filters designed with different lengths, widths, and depths. Installing an air conditioning filter that is not the right size can cause harmful contaminants to get into your air and dust and dirt to build-up on the coils of your A/C unit. Build up on the coils in your A/C unit can lead to costly cleaning and repairs.

Where are furnace filters located?

A/C filters are typically installed in or near your furnace. Depending on the design of your house or building, you will find your air return located in the wall, ceiling, and sometimes in the floor. In most cases, you will have an air return located on each level of your home or business.

How to Measure Furnace Filters

You can find what size A/C filter you need by looking for printed numbers along the side of your existing filter. If your filter doesn’t have the size printed on the side, you can measure the filter yourself to find out what size filter you need. When measuring your filter, you will get what is called an actual measurement. These measurements will usually include ¼ or ¾. When shopping for A/C filters online or in store, you will usually see what is called the nominal measurement. If you are having a hear time finding what size filter you need, round up the actual measurement of your filter to find the right nominal size of your air conditioner filter.

What is a MERV Rating?

Once you know what size A/C filter, you will need to determine which MERV rating is right for you. The Minimum Efficiency Reporting Value also known as MERV is the industry standard set by the American Society of Heating, Refrigeration and Air Conditioner Engineers. The MERV rating of a filter rates its overall performance. Sometimes you will see FPR or MPR ratings too. You can learn more about the differences in between filter ratings on The Filtered Files Blog. We’ll keep it simple for you: the higher the MERV rating number, the more airborne particles it will capture. For residential application, we recommend MERV 11 A/C Filters.

Not sure what MERV rating you should use? Check out our MERV Rating Chart.

Air Conditioner Filter Maintenance

A/C filters should be changed every 1-3 months for maximum efficiency. You’ll never have to remember what size filter you need or when to change your A/C filter when you sign up for our Home Filter Club A/C Filter Subscription! Once you find the A/C filter you need, select how often you would like to have them delivered and we’ll take care of the rest!