GOC333288 - 2 - VF Drives for Supply and Return Fans

Install variable frequency drives (VFD's) on the supply and return fans of the 2 main air handling units (AHU). The two main AHU's are variable volume fan systems (VAV). They supply air to VAV boxes on the floors providing zone control to the tenant. They have the ability to vary the amount of airflow to the space based on demand by varying the pitch of the fan blades. This method of flow control does not provide much motor electricity savings since the motor still runs at full speed. Savings can be achieved by installing VFD's to control the airflow. This method reduces the motor energy use considerably and provides better control on the supply airflow, thus allowing for better zone control and comfort. P&S in 1st year and implementation in 2nd year.