Supply Air Static Reset

This program and associated wiresheet will allow you to add supply air static pressure set point reset control based on a min and max VAV damper position. (Supply Fan Pressure Optimization)

What is Supply Fan Pressure Optimization?

When communicating controllers are used on the VAVs, it is possible to optimize this supply static pressure to minimize duct pressure, and save fan energy. Each VAV unit controller knows the current position of its air damper. The BAS continually polls these controllers, looking for the VAV with the most-open damper (Critical Zone). The static pressure set point for the supply fan is then reset to provide just enough pressure so that this most-open VAV damper is nearly wide open (85-95% open). This results in the supply fan generating only enough static pressure to push the required quantity of air to this "critical" VAV.

Installation

The ZIP file contains a single BOG file. Extract and add the BOG to your station by dragging it from your files to the station via the Niagara Workbench Nav Tree.

Usage

1. Add the wiresheet and program object to your station

2. Adjust the execution time and set points

   • Use the defaults to get started

3. Link in your maximum VAV damper position to the NumericWritable named VAVDamperMaxPos

4. Set the reset control to enabled

5. Link the set point (NumericWritable named PressureSept) to your AHU or RTU

Copyright 2020 NiagaraMods