Furnace Filters

There are many things that we do daily to stay healthy like brushing our teeth, washing our hands, and drinking plenty of water. One thing we don't usually think about, but is essential to our overall wellness, is purifying our indoor air. Air filtration is an important part of our daily lives because it helps keep us from getting sick and it protects our HVAC system too. Filters capture the things that we don't want in our air or in our HVAC system like dust, dirt, pollen, and more. If your health and air quality are important to you, invest in a pleated air filter today!

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It is printed on the product label of your filter. Once you've identified the part number, enter it in the filter finder above.

Why Should You Replace Your Furnace Filter?
The key to creating a healthy environment in your home or business is changing your furnace filter at least every 90 days. Pleated air filters not only prevent airborne contaminants like dust, pollen, mold spores, bacteria, pet dander, and other allergens from getting into your air, they also increase the efficiency and longevity of your air system, reduce energy bills, and improve airflow. Furnace filters, air filters, AC filters, HVAC filters— no matter what you call them are all the same. FiltersFast.com is your one-stop shop to buy replacement filters online.
What Size Furnace Filter Do You Need?
When it comes to filters, size is of the utmost importance. There is no "one size fits all" for furnace filters. Filters come in different lengths, widths, and depths. Making sure you have the correct size air filter is so important. Why? Because installing the incorrect size filter can cause harmful contaminants to get into your air and allow dust and dirt to build up on your furnace coils which can lead to costly cleaning and repairs.
Where Are Furnace Filters Located?
Furnace 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. Typically, you will have a return for each level of your home or business.
How to Measure Furnace Filters
Your furnace filter’s size is usually printed along the side of your existing furnace 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 you measure your filter, you will usually find that these measurements include ¼ and ¾ measurements which is called the actual measurement. When shopping for furnace filters, you will usually see nominal measurements listed. Round up the actual measurement of your filter to find the right nominal size of your furnace filter.
What is a MERV Rating?
After figuring out what size furnace filter you need, the next step is to select the MERV rating you need. MERV stands for Minimum Efficiency Reporting Value. MERV is the industry standard set by the American Society of Heating, Refrigeration, and Air Conditioner Engineers that rates the overall performance of a filter.

Sometimes you might see a rating other than MERV listed, like FPR or MPR. You can learn more about the differences in the ratings on The Filtered Files Blog. The higher the MERV rating, the more airborne particles it will capture. We recommend MERV 11 for residential application, but MERV 13 and MERV 8 are also great options to improve the quality of your home's air.
Picture of a stack of filters