When the unit Occupancy state is UNOCCUPIED, the fan starts and runs at minimum
speed only on a call for heating. The fan starts when the Heating loop is greater than 5% and
stops when the Heating loop is less than 1%.
Illustration 7–3 Parallel fan operation
MAX FAN SPEED
MIN FAN SPEED
FAN OFF
OCCUPIED
HTG SP ROOM TEMP INCREASE
UNOCCUPIED/
STANDBY
Reheat sequence
The SimplyVAV controllers can control four types of reheat installations.
l Modulating reheat
l Staged reheat
l Time proportioned reheat
l Floating reheat
All reheat is controlled by either the Heating loop or the Discharge Air Temp Limiting (DAT)
PID loop. Loops are described in the topic PID control loops on page 52.
l If Discharge Air Temp Limiting is enabled, reheat is controlled by the DAT PID loop.
l If DAT control is not enabled, reheat is controlled by the Heating loop.
In the following descriptions, the loop controlling reheat is referred to as the Reheat loop.
SimplyVAV Section 7: Sequences of operation
Revision H 57
To Next Page
Loading...
