COBP system strategies - Verasys - LIT-12012370 - Building automation software - Verasys System

Verasys System Operation Overview Technical Bulletin
Brand
Verasys
Product name
Verasys System
Document type
Technical Bulletin
Document number
LIT-12012370
Revision date
2020-07-01
Product status
Active
Language
English

CO2 DCV Operation

Note: DCV operation is not supported on split-system equipment.

RTU

When the CO2 level in an individual zone exceeds above its CO2 setpoint, the VZC increases the minimum position of the economizer damper by 5% every 30 minutes. When the zone has fallen below the setpoint for 5 minutes, the coordinator decreases the economizer minimum position by 5% every 30 minutes. The economizer minimum position is never increased beyond the user-adjustable maximum ventilation damper position and is only decreased to the user-adjustable economizer minimum position. The 30-minute time period is reduced to two minutes when the Title 24 Test Mode parameter is set to True.

Zone Damper

When Demand Ventilation Mode of Operation is set to CO2 and a CO2 sensor is reliable, the DCV minimum damper positions (DCV Cooling Min Value and DCV Heating Min Value) are proportionally reset based on a CO2 setpoint and a CO2 proportional band. The damper minimum flow reset does not exceed the user-set maximum value (Demand Ventilation Maximum Economizer Position). If the CO2 sensor is unreliable, the system uses the Damper Cooling Min Position and Damper Heating Min Position.