Why is a minimum damper position important in outdoor air control?

Why is a minimum damper position important in outdoor air control?

• A. It seals off outdoor air completely.
• B. It only affects heating, not ventilation.
• C. It ensures baseline ventilation rate and prevents air quality from dropping when zone calls are low.
• D. It increases energy use.

Answer: (C)

Maintaining a minimum outdoor-air damper position ensures a baseline supply of outside air at all times, even when the space isn’t calling for heating or cooling. This guarantees a consistent ventilation rate, which dilutes indoor contaminants and helps meet ventilation standards. When zone calls are low, the damper could otherwise close too far and air quality would deteriorate; the minimum setting prevents that by always bringing in some outdoor air. That’s why this option is best: it protects indoor air quality and maintains the required baseline ventilation, rather than sealing off outdoor air completely, affecting only heating, or increasing energy use as the primary purpose.

Maintaining a minimum outdoor-air damper position ensures a baseline supply of outside air at all times, even when the space isn’t calling for heating or cooling. This guarantees a consistent ventilation rate, which dilutes indoor contaminants and helps meet ventilation standards. When zone calls are low, the damper could otherwise close too far and air quality would deteriorate; the minimum setting prevents that by always bringing in some outdoor air.

That’s why this option is best: it protects indoor air quality and maintains the required baseline ventilation, rather than sealing off outdoor air completely, affecting only heating, or increasing energy use as the primary purpose.