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MERV Ratings
02-20-2020

What Are the Differences Between MERV Ratings?

When it’s time to buy, upgrade or replace your HVAC’ System’s air filter it’s important to understand and know about MERV ratings and their role in indoor air quality of your home. MERV stands for Minimum Efficiency Reporting Values which was developed by the American Society of Heating, Refrigeration and Air Conditioner Engineers – ASHRAE. This value lets us know the size of particles, ranging from 0.3 and 10 microns, an air filter is designed to catch. In general, the higher the MERV rating, the better the filter is at collecting particles. MERV ratings range from 1 to 16. It’s important to find the right MERV filter for your HVAC system since too high of a MERV can cause air restriction making your system work harder which can decrease the efficiency of your unit.

If you are unsure of you air filters MERV rating, you can typically find it on the top section of a used filter. Keep in mind, this may vary depending on the brand and size of your filter. However, when buying a new filter, you can count on the MERV rating being located on the packaging. So now that you know what MERV ratings are let’s talk more about what each rating means and particles it traps from your air.

MERV Rating 1-4

The lowest category of MERV ratings falls in between the values of 1 and 4. These filters are typically the standard fiberglass 1” filters most HVAC systems come with, however, collect less than 20 percent of particles that are sized between 3 and 10 microns. Examples of these particles include pollen, standing dust, dust mites, spray paint dust, and carpet fibers.

MERV Rating 5-8

This mid-level MERV filter category are mostly pleated and captures particles that range from 3 to 10 microns in size. Filters in this range will trap anywhere between 20 percent, on the lowest MERV rating of 5, up to 85 percent of particles, at the highest range of MERV 8. Particles that fall into this category include those above as well as fabric protectors, cooing dust, cement dust, hair spray, and mold spores.

MERV Rating 9-12

Also, in the mid-level of the MERV rating system, these filters trap particles ranging in size from 1 to 10 microns. For those particles sized in between 1 and 3 microns, these filters will trap from 50 up to 89 percent of the particles present. For the particles 3 to 10 microns in size, the efficiency of particle trapping runs 85 percent and better. This category will capture all the above mentioned and additional particles like pet dander, lead dust, milled flour and bacteria.

MERV Rating 13-16

The highest of the MERV ratings for HVAC filters, this category includes particles ranging from .03 to 10 microns in size. MERV 13 is the highest recommended filter for residential homes. On the smaller end, 75 percent or more of the particles between .03 and 1 micron in size are collected by these filters. For particles in between 1 and 10 microns in size, the efficiency of these filters is 90 percent or better. HVAC filters with a MERV rating in this category collect all the particle examples listed above as well as tobacco smoke, sneezes, and smog (pollution) and attached viruses.

Call Us Today

Understanding the MERV rating of your HVAC system’s air filter and how it affects the air quality in your home is very important. According to AprilAire, to achieve a healthy home, be sure to consider what type of air filters you use and how efficient they are at removing air particles to increase indoor air quality. This will go a long way toward making sure your family’s respiratory wellness is secure while staving off allergy and asthma triggers. Lastly, steer clear of generic-brand air filters that sacrifice quality and efficiency.

At Christian Heating and Air Conditioning, Inc., we recommend Aprilaire air filter products to keep the air quality in your home clean and safe to breathe. If you're having trouble or you simply need some advice about which Aprilaire filter is best for your home and family needs, then give us a call today at (215) 372-8636. Our Customer Service Team can answer all your questions, and assist you in determining which air filter is right for you.