Which description best matches a VAV with zone sensing control?

Which description best matches a VAV with zone sensing control?

• A. It relies on manual operator adjustments only
• B. It adjusts zone airflow based on zone temperature feedback to maintain setpoint
• C. It uses only a single damper position for all zones
• D. It controls air velocity by fixed-diameter ducts

Answer: (B)

The main idea here is that a VAV with zone sensing uses feedback from each zone to control how much air that zone receives. Each zone has its own sensor and controller, which compares the sensed temperature to the desired setpoint. When a zone needs more cooling or heating, the damper for that zone opens or closes accordingly, adjusting the amount of supply air delivered to that specific zone. This per-zone modulation lets the system maintain the target temperature more precisely and efficiently, rather than pushing the same amount of air to every zone. This description fits best because it highlights the zone-level feedback loop driving the damper positions, producing the required airflow to meet each zone’s temperature setpoint. It explains why the system isn’t just manually adjusted or using a single damper for all zones, and it aligns with how zone sensing directs airflow through the VAV boxes to achieve localized comfort. In contrast, relying solely on manual operator adjustments ignores automatic feedback; using a single damper position for all zones ignores zone-specific loads; and controlling air velocity through fixed-diameter ducts doesn’t capture the fundamental VAV principle of modulating airflow by damper position in response to zone conditions.

The main idea here is that a VAV with zone sensing uses feedback from each zone to control how much air that zone receives. Each zone has its own sensor and controller, which compares the sensed temperature to the desired setpoint. When a zone needs more cooling or heating, the damper for that zone opens or closes accordingly, adjusting the amount of supply air delivered to that specific zone. This per-zone modulation lets the system maintain the target temperature more precisely and efficiently, rather than pushing the same amount of air to every zone.

This description fits best because it highlights the zone-level feedback loop driving the damper positions, producing the required airflow to meet each zone’s temperature setpoint. It explains why the system isn’t just manually adjusted or using a single damper for all zones, and it aligns with how zone sensing directs airflow through the VAV boxes to achieve localized comfort.

In contrast, relying solely on manual operator adjustments ignores automatic feedback; using a single damper position for all zones ignores zone-specific loads; and controlling air velocity through fixed-diameter ducts doesn’t capture the fundamental VAV principle of modulating airflow by damper position in response to zone conditions.