Application of Fan Airflow Stations In Air-Handling Units

ABSTRACT This article demonstrates a case study in which fan airflow stations were applied to the air-handling unit's operation to improve building pressure control and reduce fan energy consumption. The fan airflow station is a new airflow measurement technology that uses fan differential pressures, fan speeds, and fan curves to measure the supply and return airflow rates more accurately than typical airflow stations used in recent air-handling units. The fan airflow stations were used as a volumetric return fan tracking method for building pressure control. The building pressure was maintained adequately positive by controlling the return airflow a little less than the supply airflow. The building pressure control was not affected by wind or any other operational conditions. The fan airflow stations were also used to reset a duct static pressure set point under partial load conditions. The set point could be reset from the calculated supply airflow ratio, which saved substantial fan power consumptions. ...