A woman holding a dirty air filter with a pair of yellow gloves

MERV: Rating an AC’s Efficiency

It can be intimidating when trying to buy a new air conditioner for your home or business. What you need in your family’s home is most likely not the same needs you’ll see in your business. It’s important to consider factors like keeping your indoor air clean. According to the American Society of Heating, Refrigerating, and Air Conditioning Engineers, the process of filtration helps provide healthier indoor air quality. So, how do you even start? In this blog, we’ll break down the term MERV and how it can help you decide what unit is best for your needs.

What is MERV?

When shopping for a new air conditioner, you may have encountered the term MERV. MERV stands for Minimum Efficiency Reporting Value and is a way to measure how well an AC unit can filter out particles in the air. The higher the MERV rating, the more efficient the AC unit is at filtering particles.

MERV ratings range from 1 to 20. AC units with a MERV rating of 1 to 4 are typically used in homes without pets or smokers. These units do a good job of removing large particles from the air, such as dust and pollen. AC units with a MERV rating of 5 to 8 are better at removing smaller particles, such as mold spores and pet dander. Finally, AC units with a MERV rating of 9 to 16 are used in homes with smokers or people with allergies. These units do an excellent job of removing small particles from the air.

When shopping for a new AC unit, be sure to check the MERV rating. This will help you choose an AC unit that is right for your home and your family’s needs.

Breaking Down MERV Ratings Further

MERV 1 - 4

  • It is commonly used to trap pollen, dust mites, sanding dust, carpet, and other fabric fibers.

  • Commonly used in window air conditioner units and residential furnaces.

MERV 5 - 8

  • What is listed above plus mold, dust lint, and cement dust

  • Commonly used in paint booths, industrial workspaces, and higher-end residential buildings.


MERV 9 - 12

  • All of the listed above plus, legionella, lead dust, humidifier dust, coal dust, and nebulizer dust.

  • Commonly used in hospital labs, and higher-end commercial buildings.

  • This range is also most recommended to be used in homes.

MERV 13 - 16

  • In addition to the above listed, this air filter can trap bacteria, smoke, auto fumes, allergens, pet dander, and face powder.

  • Most commonly used in places where you can smoke inside, general surgery, and hospital inpatient care rooms.

MERV 17 - 20

  • In addition to the above listed, this MERV rating is also used to trap viruses, carbon dust, sea salt, combustion smoke, odor, and microscopic allergens.

  • These filters are most commonly used in surgery rooms, pharmaceutical manufacturing factories, nuclear power plants, and sometimes classrooms.

How We Can Help

Our team of certified HVAC technicians is available to provide a wide range of air conditioning services. If you are considering upgrading your system but not sure what model is right for you, our team can use their expertise to ensure your home or business is equipped with the perfect unit to fit all of your needs. We have over 20 years of experience providing our customers with excellent service. We also offer repair services and can check if you’re using the right air filter for your home or business. Using the wrong air filter can lead to a spike in your energy bill and decrease the lifespan of your HVAC unit, so it’s important to check that you’re using the right one. Don’t hesitate to reach out today!

For all of your indoor air needs and questions contact Rainforest Plumbing and Air at (602) 755-2995!Your guide to a 5-star experience. Proud to serve Phoenix & Tucson, AZ since 1999.