eZV-440 Version 2.1 Application Guide
Page 54 of 67
Document Edition 2.5
Space demand
Box Mode
Airflow Setpoint
Airflow setpoint = AirflowDemand x (CoolingMaximum –
CoolingMinimum) + CoolingMinimum
If there is no space heating or cooling demands, the airflow setpoint is the value of the
StandbyMinimum field on the Setpoints tab (AV129) in Standby occupancy mode; in Unoccupied
occupancy mode, the airflow setpoint remains at zero.
Air Balancing
The airflow setpoint also changes during air balancing. When you select an option on the
Balancing Mode field, the air flow setpoint is set to the following values:
Balancing Mode option
Air Flow Setpoint (AV830) set to:
ClgMinFlow_
CoolingMinimum
ClgMaxFlow_
CoolingMaximum
HtgMinFlow_
HeatingMinimum
HtgMaxFlow_
HeatingMaximum
Demand Control Ventilation
Demand control ventilation (DCV) control sequence determines the amount of fresh air in the
space. The sequence only operates during occupied modes and is disabled when the building is
unoccupied. To use the DCV algorithm, on the Local Inputs tab of the configuration graphic, you
should have a CO
2
input (AV3) set up with the DemandVentEnable setting (BV103) turned on.
You should also enter a CO
2
demand setpoint in the CO2DemandVentSetpoint (AV185) field.
The CO
2
demand is reflected in the demand control ventilation (AV813) object. The algorithm
determines the airflow setpoint needed to meet this demand. The demand increases when the