What does MERV stand for, and how does increasing MERV affect filtration and system airflow?

What does MERV stand for, and how does increasing MERV affect filtration and system airflow?

• A. Minimum Efficiency Reporting Value; higher MERV improves filtration but increases resistance and may reduce airflow if the system is not adjusted.
• B. Maximum Efficiency Rating Value; higher MERV improves filtration and always increases airflow.
• C. Minimal Efficiency Verification Rating; higher MERV has no effect on airflow.
• D. Mosterv Efficiency Rating Value; higher MERV decreases filtration effectiveness.

Answer: (A)

MERV stands for Minimum Efficiency Reporting Value. Higher MERV ratings mean the filter can capture smaller particles, improving filtration and indoor air quality. But that finer filtration comes with more resistance to airflow, increasing the system’s pressure drop. If the HVAC system isn’t adjusted to compensate—for example, by increasing blower speed or using equipment with enough flow capability—the airflow can be reduced. So the best answer captures both parts: better filtration with higher MERV, and the potential for reduced airflow unless the system is designed or adjusted to handle the added resistance.

MERV stands for Minimum Efficiency Reporting Value. Higher MERV ratings mean the filter can capture smaller particles, improving filtration and indoor air quality. But that finer filtration comes with more resistance to airflow, increasing the system’s pressure drop. If the HVAC system isn’t adjusted to compensate—for example, by increasing blower speed or using equipment with enough flow capability—the airflow can be reduced. So the best answer captures both parts: better filtration with higher MERV, and the potential for reduced airflow unless the system is designed or adjusted to handle the added resistance.