Variable Air Volume or VAV Boxes is the most common method employed in commercial/institutional buildings and is both an effective and economical means of temperature control by Regulating the Air Flow.
The simplest VAV system controls air from a single supply duct and varies the airflow to each zone or room based upon the temperature in the room.
From a control perspective, such a system would consist of a few essential components :
In some instances, these components are combined. For example, a Smart Thermostat can combine the functions of a Temperature Sensor and a Controller.