Terminal Box Airflow Reset: An Effective Operation and Control Strategy for Comfort Improvement and Energy Conservation

A new terminal box operation and control strategy, airflow reset, is developed to improve building comfort and energy efficiency during unoccupied and lightly occupied hours. The airflow reset lowers the minimum airflow possibility to zero for variable air volume (VAV) terminal boxes, and changes the airflow to a lower value for constant air volume terminal boxes (CV). It maintains zone temperatures at comfortable levels or daytime set points during unoccupied or lightly occupied hours. It decreases heating, cooling, and fan power significantly. A case study measured 40% of the design airflow reduction in the Air Handling Unit level. This paper presents airflow reset strategies, potential heating and cooling energy savings models, and implementation issues