What Is a MERV 11 Filter?

The MERV system was created by ASHRAE (American Society of Heating, Refrigerating, and Air Conditioning Engineers) to provide a rating system for the efficiency of AC filters. This rating system ranges from 1 to 20, with higher MERV ratings indicating a superior level of filtration. One of the most popular air filters is the MERV 11 filter, which balances cost and effectiveness. Keep reading to learn more about the MERV 11 filters. 

The Efficiency of a MERV 11 AC Filter

A MERV 11 filter can filter out both large and small particles from the indoor air, having a success rate of 20% in capturing particles of size 0.03 to 0.1 microns, 50% to 65% in capturing particles of size 0.1 to 3.0 microns, and 85% in capturing 0.3- to 10-micron particles. These filters can trap lint, dust particles, pet dander, debris, mold, auto emissions, smog, bacteria, fine air particles, sneeze and smoke nuclei, and pollen. It can even remove foul odors from the indoor air, improving its quality. 

MERV 11 filters are slightly more expensive than other lower MERV rating options. However, you get excellent filtration capabilities, making it the ideal choice for individuals who are sensitive to air quality or allergic to airborne contaminants. High-quality AC filters such as the FilterKing | Merv 11 filters can significantly improve indoor air quality.

How Does a MERV 11 Filter Work? 

MERV 11 filters typically comprise synthetic fibers that are bonded and layered together to trap particles of various sizes. Depending on the manufacturer, the filter media of a MERV 11 filter can vary. For example, some modern MERV 11 filters have an electrostatic charge, and these filters have an additional layer of fibers to capture contaminants more effectively. MERV 11 filters with electrostatic charge can even trap some viruses and bacteria. 

To enhance the filtration capabilities of the MERV 11 filter, some manufacturers also add features such as activated carbon. 

Due to the high level of filtration, the MERV 11 filter can become clogged faster than lower MERV rating AC filters and require a replacement. Although these filters can last for months, it is best to check the filter every 90 days and replace it if necessary. A clogged MERV 11 AC filter can restrict airflow, causing the AC system to underperform. 

Impact of MERV 11 Filter On Air Flow

Generally, AC filters with high MERV ratings can increase stress on the AC components. This can cause the AC to work harder to pull air through the filter, often leading to AC damage or poor performance. However, a MERV 11 filter does not restrict airflow. The higher number of pleats creates a larger surface area than filters with a lower MERV rating. 

Generally, if a filter has a higher number of pleats, it has better airflow. It also causes a lower-pressure drop, preventing the coil, heat exchanger, and other air conditioner parts from getting damaged.