What is the Average Air Filter Size and How to Choose the Right One?

The filters used in air conditioners and ovens are labeled with three-part dimensions. The first number is its length, the second is its width, and the third is its depth or thickness. To find the right filter size, you need to round up to the nearest inch to create the nominal filter size. This rounded measurement is called the nominal size and is used to match the correct filter to the air cleaner slot of the accessory.

How often you change the air filters in your home depends on the type of air filter you have in your home and the environmental conditions, such as smoke, dust, or construction. If you have a system that uses a whole-house filter, you may have a choice from MERV 8 to MERV 16 depending on your HVAC system. Lennox has a MERV 16 filter option as an offer on the Lennox Pureair system, which is among the highest-efficiency residential filters available. Filters are generally listed by Nominal Size, which is a rounded number, based on the actual dimensions of the filter.

They are seven times better than a standard filter for removing dust and other particles and have a longer service life than other filters (up to two more years). Improperly sized, or installed governable filter frames can cause air leaks, which significantly decreases filter effectiveness. If you use a room air purifier and need to replace the filter, it's important to find the correct size replacement HEPA filter. Of course, this sounds easy when you hear the term “standard air filter size”; you might think that if your air filter is standard, it will be easy to find it when you arrive at the store.

You can usually find the filter size of your air conditioner right in the size of the filter frame. Now instantly improve air quality by choosing the right MERV rating because your family deserves the best. Watch the video for guidance on using the oven filter size chart below and hear expert advice to make the right choice and avoid common mistakes.

Willis Diruzzo
Willis Diruzzo

Typical sushi enthusiast. Infuriatingly humble music geek. Typical internetaholic. Subtly charming social media maven. Lifelong bacon buff.