Patent attributes
A system and method for providing a substantially constant volume exhaust or ventilation air terminal system is shown for controlling exhaust and/or return airflow rates in a system having a central fan or ventilator. The system and method permits zone-by-zone or area-by-area airflow regulation or control in non-demand areas in response to a demand or call for ventilation in demand areas. In one embodiment, the system employs at least one constant airflow controller or regulator situated in a damper. Another embodiment shows a combination of a first constant airflow controller or regulator situated or mounted on a damper with a second constant airflow controller or regulator situated in a duct associated with the damper. In still another embodiment, a constant airflow controller or regulator is provided in a duct, and used in combination with a solid damper.