Introduction - Metasys - LIT-12012070 - Field Device - VAV: Variable Air Volume Controller

Air Handling Unit Reset Application Note

Product name
VAV: Variable Air Volume Controller
Document type
Application Note
Document number
LIT-12012070
Revision date
2018-03-01

This application note provides information on how you can install the Logic Connector Tool (LCT) Air Handling Unit (AHU) Reset application on an AHU with Variable Air Volume (VAV) boxes. The application uses a trim-and-respond method to reset the AHU discharge pressure and temperature setpoints based on the corresponding VAV box demand. For systems with direct digital control (DDC) at the zone level, ASHRAE Standard 90.1 and California's Title 24 Energy Standards require the discharge air static pressure setpoint to be reset based on the zone requiring the most pressure. To maximize energy savings, the application resets only the discharge air static pressure in the summer mode and only the discharge air temperature in the winter mode. You can easily modify the application to reset only the discharge air static pressure at any time.