MERV stands for Minimum Efficiency Reporting Value, and it is a standard rating system used to measure the effectiveness of air filters in trapping and removing airborne particles from the air. The MERV rating scale typically ranges from 1 to 20, with higher numbers indicating a higher level of filtration efficiency. A higher MERV rating means that the filter can capture smaller particles, providing better indoor air quality.

A higher MERV-rated filter tends to restrict more airflow than a lower MERV-rated filter. While this higher level of filtration is beneficial for improving indoor air quality by capturing more pollutants, it can also lead to increased resistance to airflow. As a result, HVAC systems may need to work harder to push air through the filter, potentially causing a decrease in airflow. This is an example where a Variable Speed system is able to compensate for airflow restrictions but adjust the blower speed to overcome this added resistance and maintain optimal comfort and operational efficiency. Remember to check your filters regularly! Easy rule of thumb, make filter changes part of your seasonal home maintenance (Every 3 months, Spring, Summer, Fall, Winter).