enteliZONE Sequence of Operations
Page 68 of 84 eZV-440 Application Guide
Edition 2.6
HeatingMinimum = minimum heating airflow setpoint
CoolingMinimum = minimum cooling airflow setpoint
AirflowDemand = Airflow demand in % (AV808)
At no time can CoolingMaximum be lower than CoolingMinimum or CoolingMinimum be greater
than CoolingMaximum but they can be the same.
HeatingMaximum can never be lower than HeatingMinimum and HeatingMinimum can never be
greater than HeatingMaximum. But HeatingMaximum and HeatingMinimum can be equal to each
other.
The following table shows the damper staging order and how airflow setpoint is calculated:
Space
Demand
Box Mode Airflow Setpoint
Heating
demand
AutoHeat
(Hot air in the
duct) or
HeatCmd in
manual mode
Damper is the first stage of heat.
As the Airflow Demand increases from 0 to 100%, the airflow
setpoint increases from the HeatingMinimum to the
HeatingMaximum setpoint.
Airflow setpoint = AirflowDemand x (HeatingMaximum -
HeatingMinimum) + HeatingMinimum
Heating
demand
AutoCool
(Cool air in
the duct) or
CoolCmd in
manual mode
If there is a duct reheat stage and no series or parallel fans, the
damper is the last stage of heat. As the Airflow Demand
increases from 0 to 100%, the airflow setpoint increases from
the HeatingMinimum to the HeatingMaximum setpoint.
Airflow setpoint = AirflowDemand x (HeatingMaximum -
HeatingMinimum) + HeatingMinimum
For fan-powered VAV boxes, the damper airflow setpoint is
maintained at the CoolingMinimum setpoint and the fan
provides any additional airflow for the duct heater.
Cooling
demand
AutoHeat
(Hot air in the
duct) or
HeatCmd in
manual mode
The damper has no cooling capacity as there is hot air in the
duct. The airflow setpoint is fixed at the CoolingMinimum
setpoint.
Airflow setpoint = CoolingMinimum
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