Optimal Terminal Box Control for Single Duct Air-Handling Units

Abstract

Terminal boxes maintain room temperature by modulating supply air temperature and airflow in building HVAC systems. Terminal boxes with conventional control sequences often supply inadequate airflow to a conditioned space, resulting in occupant discomfort, or provide excessive airflow that wastes significant reheat energy. In this study, an optimal terminal box airflow control sequence was developed to improve indoor ventilation and reduce energy consumption. The developed control sequence was applied in an office building air conditioning system. Improvements in indoor thermal comfort and energy reduction were verified through measurement. The results show that the optimal control sequence can stably maintain thermal environment, satisfy comfort standards and reduce energy consumption compared to the conventional control sequence.