Application 2567 Vav Parallel Fan Powered With Hot Water Reheat; Overview; Fan Operation - Siemens BACNET 125-5037 Owner's Manual

Applications
Application 2567 VAV Parallel Fan Powered with Hot
Water Reheat

Overview

In Application 2567, the controller modulates the supply air damper of the terminal box to
provide for cooling and modulates a hot water valve for heating. When in heating, the
terminal box either maintains minimum airflow or modulates the supply air damper. The
terminal box also has a parallel fan that re-circulates the room air. In order for the terminal
box to work properly, the central air handling unit must provide supply air. See Figure 14.

Fan Operation

The fan turns on when heating is required.
3 to 5 Straight Duct Diameters
required for proper sensor reading
18
Recirculated
Plenum Air
Air
Velocity
Sensor
Supply Air
Valve
Actuator
Figure 14. Application 2567 Control Drawing.
Recirculated
Air Damper
Fan
Supply
Air Damper
Spare DO
"COMMON" Termination for all DOs
RTS
FLN
Hi/Lo Tubing
Connections
SAFETIES
BY
OTHERS
Modulating
Damper
Actuator
NO
BACnet Actuator
Controller
Siemens Building Technologies, Inc.
Wall Switch (Opt.)