An HVAC unit’s air filter should be changed often. Generally, it is recommended that it should be changed every 3 months. HVAC filters play a significant role in maintaining indoor air quality and energy efficiency. Having a dirty, clogged, or broken air filter will hurt the unit and cause the system to work harder than it should be. According to a 2009 study by the American Society of Heating, Refrigeration and Air Conditioning Engineers, HVAC filters can reduce efficiencies by 10 percent or more.


What is MERV, MPR, FPR?

MERV stands for Minimum Efficiency Reporting Value. In laymen’s terms, it’s a rating created by the American Society of Heating, Refrigerating, and Air-Condition Engineers (ASHRAE) which ranks an air filter’s effectiveness on a 1-16 scale. One is the least effective filter and 16 is the most effective. The higher the MERV rating, the less likely it is that dust, pollen, carpet fibers, and contaminant particles will be able to pass through the filter and into your heating and cooling system.

The other two systems were created by “3M” (MPR) and “The Home Depot” (FPR) to differentiate their offerings. However, at the end of the day, the ratings apply to the SAME filters and can be used in your furnace or AC unit!


No matter what type of HVAC system your home has, it most likely has an air filter. The purpose of an air filter is to remove particulates from the air.

When it comes time to replace your air filter, figuring out the size of your air filter isn’t the only thing you need to do. You also need to figure out what the best air filter MERV rating is for your situation. Contact us, our experts can help you choose what’s best for your home!

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