MERV Rating on Air Filters: What It Is and Why It Matters

Minimum Efficiency Reporting Value
“MERV.” Sounds like the name of a TV producer or an annoying neighbor! But when it comes to air conditioning, the acronym MERV stands for Minimum Efficiency Reporting Value.
What that Means
The MERV rating on an air filter was designed by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) to rate the effectiveness of air filters. In other words, MERV ratings indicate an air filter’s ability to remove pollutants from the air. So the higher MERV rating, the higher its performance.
We think clean air is important. And most would agree that everybody wants to breathe clean air. So we’ll never stop reminding you about the importance of changing your air filters. It’s good for your health, as well as for the health of your air conditioning system. The MERV rating on an air filter serves as a guide for making a purchasing decision. Factors to consider when choosing an air filter include whether anyone in your home suffers from allergies; whether you have pets in your home; and of course, the cost of the air filter.

Higher Rating – Higher Efficiency
The MERV rating is determined by comparing the filter’s efficiency to the particle size it can capture. So again, the higher the MERV rating, the more efficient it is. The most recommended MERV ratings for residential filters are between MERV 7 and MERV 13. Most airborne contaminants can adequately be removed with an air filter within those ratings.
Anything higher than a MERV 13  is typically found in a hospital environment, where air sanitation is of the highest importance. Most air filters of MERV 6 or higher are effective at trapping dust, mold spores, tobacco smoke, pet dander and pollen. Anything below that, good luck breathing! The MERV rating of an air filter probably doesn’t mean a whole lot to the average person. But if you’re a person dealing with pets or allergies, then you should care more. Higher-rated filters are beneficial to those who are chronically ill; have respiratory conditions; or live with family members who have health issues.
MERV Ratings Breakdown
MERV 6-8
These air filters are the cheapest ones and are considered the bare minimum of efficiency. MERV 6-8 filters protect your HVAC system, but are not considered the most effective at catching large portions of airborne particles. So if anyone in your home has allergies or a respiratory condition, you should consider getting a higher MERV air filter. Filters with a MERV 6 rating are more affordable and will do the job for the most part, as long as you don’t have furry pets or ashtma.
MERV 8-10
These air filters are also common for household use and are still fairly affordable. But MERV 8-10 filters capture more of the large particles and at least half of the smaller particles like pollen, mites, and mold and mildew spores. These air filters are also a more affordable option for allergy sufferers than higher MERV filters. So if you’re looking for a high quality common household air filter that’s efficient with airflow, then a MERV 8-10 filter is all you really need.
MERV 11-13
MERV 11-13 air filters are somewhat of a middle ground between the cheap ones and the more expensive ones. They capture nearly all of the largest particles, as well as most of the smallest ones. If you have pets and dander is an issue, a MERV 11-13 will be much more effective at cleaning your indoor air. These air filters are also highly recommended if you or anyone in your family has heavy allergies or asthma. And they provide highly effective residential air filtration for a much healthier breathing environment.
MERV 13 air filters are considered the best overall for residential HVAC systems. Schools commonly use MERV 13 air filters to provide clean learning environments for their students and staff. It’s worth noting that anything higher than MERV 13 is not recommended for residential use. MERV 13 air filters are highly effective at removing a higher range of particles including smoke, bacteria and even some viruses. They’re perfect for people who are prone to illness and need the cleanest, most sterile environment possible.
MERV 14 and higher
These air filters are incredibly efficient, but are not recommended for residential use. They’re large and bulky, and are designed primarily for heavy duty filtration in places such as medical facilities. However, air filters with MERV ratings above 13 tend to restrict airflow. That’s because they have smaller pores to capture smaller particles. A MERV 14 or higher air filter can create more resistance in airflow than a residential HVAC system is designed to handle. And a reduction in the air flow of your system can worsen the air quality in your home, as well as put too much pressure on your AC system.
Before shopping around for higher efficiency air filters, do your research. Make sure the air filter you purchase is not too efficient for the size of your AC system. Also keep air flow restriction in mind. And if you don’t have pets or any respiratory problems, do you really need to spring for a super high efficiency air filter? Remember too that higher MERV air filters need to be changed more often to avoid restricted airflow that can damage your AC system.
Not sure which air filter is right for your air conditioning system? Call us and we’ll be more than happy to help you out!

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