Trane Tracer VV550 Installation, Operation And Maintenance Manual page 60

Sequence of Operations
A ventilation flow controller in the occupied mode uses the communicated ventilation
setpoint or the configured ventilation setpoint for the airflow setpoint. A ventilation flow
controller in the unoccupied mode uses zero for the airflow setpoint.
The ventilation flow control uses nviVentSetpt if it is valid. If nviVentSetpt is not valid, the
ventilation flow control uses one of the following two airflow setpoints:
•
•
Pressure dependent (PD) mode uses the configured minimum position setpoint to
position the air valve unless the air valve should be closed.
If the controller is cooling, the active maximum airflow setpoint is the configured
maximum airflow. Otherwise, the active maximum airflow setpoint is the configured
maximum heating airflow.
The active minimum airflow setpoint must be less than the active maximum airflow
setpoint. The active minimum airflow setpoint and the active maximum airflow setpoint
are limited to 1.2 times the configured nominal airflow.
temperature controller active minimum airflow setpoint selection.
Table 40.Space temperature controller active minimum airflow setpoint selection
a
PD STC mode
Do not Off
care
No Occupied
cool
Occupied
heat
60
If no reheat being used, it uses the configured Ventilation Setup Occupied Setpoint;
If reheat being used, it uses the configured Local Heat Minimum Airflow.
Effective Control
occupancy action 
b
mode (PAT)
Do not care Do not care
Occupied Cooling
Heating
Standby Cooling
Heating
Local
reheat Active minimum setpoint (the greatest of the
state following)
Do not 0
care
Off • Configured minimum airflow
• Ventilation minimum airflow
On • Configured minimum local heating airflow
• Configured minimum airflow
• Ventilation minimum airflow
Off • Configured minimum heating airflow
• Ventilation minimum airflow
On • Configured minimum local heating airflow
• Configured minimum heating airflow
• Ventilation minimum airflow
Off • Configured standby minimum airflow
• Ventilation minimum airflow
On • Configured minimum local heating airflow
• Configured standby minimum airflow
• Ventilation minimum airflow
Off • Configured standby heating minimum airflow
• Ventilation minimum airflow
On • Configured minimum local heating airflow
• Configured standby heating minimum airflow
• Ventilation minimum airflow
Table 40 below shows space
CNT-SVX17G-EN