The acronym MERV stands for Minimum Efficiency Reporting Value, and it is a standard rating used to measure the overall effectiveness of an air filter. This value is useful for comparing the performance of different filters, as it indicates the ability of a filter to capture particles larger than 0.3 to 10 microns (µm).The MERV classification system is designed to determine the filter's ability to remove particles from the air. The higher the MERV index, the less particles and other contaminants can enter your home. Basically, the higher the MERV rating, the greater the air filtration capabilities of a particular filter. It is recommended that you check your air filters once a month to see if they are dirty enough to change them.
If the air cleaner is on the return grille of the house, the arrow should point to the wall or ceiling. Conversely, a high MERV rating indicates that the filter does a good job of removing particles from the air. E1, E2 and E3 particles are particle range sizes used to test air filters to determine the MERV rating. MERV 6-8 filters protect your air conditioning system, but are not considered to be the most effective at trapping large portions of particles in the air. Since a high MERV rating means that more particles will be removed from the air, you can first consider using air filters with the highest MERV rating. According to this article, there is a well-established connection between higher concentrations of particles in outdoor air and poor health outcomes, so it would make sense that filtering these particles out of indoor air could lead to better health outcomes.
The ASHRAE 52.2 standard describes methods and procedures for evaluating the performance of air filters based on particle size. While simple, changing air filters regularly has far-reaching implications, such as better system efficiency, longer system life and a cleaner home environment. This reduction in airflow to your air conditioning system can worsen the air quality in your home and put too much pressure on your air conditioning system. While MERV 11 filters are slightly more expensive, costing just a few dollars, indoor air quality can be improved to help relieve people with respiratory problems. With Filter King's filter selection tool, you can mark exactly the size, thickness and MERV rating you're looking for.