Abstract: An energy efficient air flow control system includes exhaust devices of a building air flow management system. Each of the exhaust devices includes a controller for controlling functions of its respective exhaust device. A first sensor is coupled to each of the exhaust devices and respective controllers. A computer is coupled to the exhaust devices via respective controllers. A second sensor determines a fan speed of a supply air fan, and the second sensor is coupled to the computer. Logic executable by the computer receives user-selected settings for controlling operation of the exhaust devices, collects data from the controllers via corresponding first sensors and from the second sensors, applies the data to the settings, and modifies operation of the system via a controller of at least one of the exhaust devices when, in response to applying the data, it is determined that a condition defined in the settings is met.