Supply Fan Compensation & Minimum Position Setting

Supply Fan Compensation (Default) 

The outdoor air damper minimum position is modulated to provide outdoor air based on supply fan speed. When the supply fan increases speed, the outdoor air damper minimum position is reduced to prevent over ventilation. When the supply fan decreases speed the outdoor air damper minimum position is increased to maintain design outdoor air requirements. There are three user editable design minimum settings to linearize damper position with the fan curve during Occupied and Occupied Bypass modes of operation. 

• Design Minimum OA Damper Position at Min Fan Capacity (25 percent default)
• Design Minimum OA Damper Position at Mid Fan Capacity (15 percent default)
• Design Minimum OA Damper Position at Full Fan Capacity (10 percent default)

Using the Symbio Phone App

• Connect to the Symbio™ 700 board through Bluetooth.
• Select the Settings menu.
• Select View Configuration.
• Scroll down to the Fresh/Return Air section.

Using the Symbio 700 Onboard menu and keypad

1. Press Home.
2. Press the Down Arrow and select Settings.
3. Press the Check.
4. Press the Down Arrow and select Fresh/Rutrun Air.
5. Press the Check.
6. You will see Design Minimum OA Damper Position at Min Fan Capacity (25 percent default), Press the Check to change the percentage, or Press the Down Arrow for the next selection. (IF you enter the selection and make a change, Press the Check to Save the change)
7. For Design Minimum OA Damper Position at Mid Fan Capacity (15 percent default), Press the Check to change the percentage, or Press the Down Arrow for the next selection. (IF you enter the selection and make a change, Press the Check to Save the change)
8. For Design Minimum OA Damper Position at Mid Fan Capacity (15 percent default), Press the Check to change the percentage, or Press the Down Arrow for the next selection. (IF you enter the selection and make a change, Press the Check to Save the change)

• You may not have all three Design Minimum OA Damper Positions.

Outdoor Air Minimum Position Control

Available only when supply fan compensation is disabled, this function provides a fixed damper position for minimum outdoor air requirements. The damper is controlled to a position determined by the Economizer Minimum Position Setpoint.

Using the Symbio Phone App

• Connect to the Symbio™ 700 board through Bluetooth.
• Select the Settings menu.
• Select View Configuration.
• Scroll down to the Fresh/Return Air section.

Using the Symbio 700 Onboard menu and keypad

1. Press Home.
2. Press the Down Arrow and select Settings.
3. Press the Check.
4. Press the Down Arrow and select Fresh/Rutrun Air.
5. Press the Check.
6. Press the Down Arrow and select Supply Fan Compensation.
7. Press the Check.
8. Change the Supply Fan Compensation from Enable to Disabled.
9. Press the Check.

• Economizer Minimum Position Setpoint BAS (25 percent default)

Symbio Precedent Application Guide

• Precedent - Symbio® 700 controller - Application Guide – Trane Commercial HVAC Help Center

WARNING:

Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.