What Is a MERV Rating for Air Quality? - Ernst Heating & Cooling

What Is a MERV Rating for Air Quality?

MERV rating

Have you heard of a MERV rating? No, MERV doesn’t stand for the game show host your grandmother liked to watch in the 1970s. MERV stands for Minimum Efficiency Reporting Value, and it’s an important designation for the air filtration systems that Ernst Heating & Cooling installs in homes around southwest Illinois.

What do air filters do?

As your HVAC system circulates air around your home, it captures some of the dust, pollen and other airborne particles that can irritate your upper respiratory tract and take up residence on your home’s tabletops and other surfaces. A replaceable air filter captures the offenders as they circulate through your HVAC system, improving air quality and protecting the machinery within your HVAC system.

What are the different MERV ratings?

The various MERV ratings indicate how effective your filter is at capturing debris in the air and improving your home’s overall air quality:

  • MERV 1-4 filters offer minimal protection. They can catch dust mites, pollen or roach debris, but they don’t do much to improve air quality.
  • MERV 5-8 filters can trap between 20% and 70% of anything larger than 3 microns. (For reference, a grain of table salt is about 40 microns.) These filters will catch pet dander and mold spores, for instance.
  • MERV 9-12 filters trap up to 90% of particulates between 3 and 10 microns and a little more than 2/3 of particulates between 1 and 3 microns.
  • MERV 13-20 filters remove particulates as small as 0.3 microns, including bacteria and viruses. These are often seen in hospital settings.

Should I get the highest MERV-rated filter?

That sounds logical: A higher MERV rating = better air quality. But, higher MERV-rated filters can damage your HVAC system if it has to work too hard to pull air through the dense filter. Many homeowners opt for whole-house air filtration systems to complement their HVAC system and clean the air better than a traditional air filter can on its own.

Ernst Heating & Cooling installs Lennox Healthy Climate filtration systems, which offer residential systems with MERV ratings up to 16. If you would like to find out which air filtration method is best for you and your family, call Ernst Heating & Cooling now at 618.217.1836 to schedule an appointment, or contact us online. We want you to enjoy clean air at home.

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