HVAC Excellence Electric Heat ESCO Practice Exam

The maximum recommended return air velocity for a residential filter is 400 feet per minute (fpm). This value is important because if the air velocity exceeds this limit, it can lead to several issues including excessive noise, decreased filter efficiency, and the potential for damaging the filter media.

At velocities above 400 fpm, the air can create turbulence, which may bypass the filter or cause improper air distribution within the system. Additionally, high velocity can result in higher pressure drops across the filter, which could lead to increased energy consumption by the HVAC system. Thus, keeping the return air velocity at or below 400 fpm helps to ensure optimal performance and longevity of both the filter and the entire HVAC system.