How must air handling units installed at floor level discharge air?

Air handling units (AHUs) installed at floor level should discharge air at waist level or above to promote better air circulation and distribution throughout the space. Discharging air at these levels helps to ensure that the conditioned air can effectively mix with the ambient air in the room, improving comfort and efficiency in heating or cooling.

Discharging air at waist level or higher prevents the air from stagnating near the floor, which can lead to cold spots in winter or warm spots in summer. Additionally, this practice minimizes the disruption of debris and dust that typically accumulates closer to the ground, helping to maintain better air quality in the environment.

Options that suggest discharging air at floor level either way—over or under 10 feet—would not encourage effective mixing of air within the space and could create comfort issues. Similarly, discharging air overboard is generally not a practice associated with standard indoor ventilation systems and would not be suitable for an air handling unit in a typical application.