In the illustrated single zone HVAC system, what statement represents the relationship between the exhaust, outside air and recirculation dampers? Refer to Illustration GS-RS-09 Illustration GS-RS-09: the U.S. Coast Guard has not released this illustration.

Correct Answer: Option C — The more the exhaust and outside air dampers are open, the more the recirculation damper is closed, and vice versa.

HVAC damper modulation maintains building pressure and air quality. Increasing outside air intake requires a proportional increase in exhaust air to prevent over-pressurization, while simultaneously closing the recirculation damper to reduce the volume of return air, ensuring the system maintains a balanced mass flow of air throughout the ventilation cycle.