Outdoor Air Damper Operation - Trane Tracer AH540 Setup And Operation

Chapter 4 Sequence of operation
56
Table 19. Face-and-bypass damper operation based upon outdoor air
temperature
Outdoor air
temperature
Outdoor air tempera-
ture is greater than
face-and-bypass heat
1
modulation setpoint
Outdoor air tempera-
ture is less than-face
and-bypass heat modu-
lation setpoint
1 The outdoor air temperature must rise 3°F above the face and bypass heating
enable point before face-and bypass-heating operation is disabled.

Outdoor air damper operation

This sequence applies to both space temperature control and discharge
air temperature control.
The controller operates the modulating outdoor air damper according to
effective occupancy, outdoor air temperature (communicated or hard-
wired sensor), space temperature, effective space temperature setpoint,
discharge air temperature, and discharge air temperature setpoint.
Default minimum damper positions are provided and can be changed
using the Rover service tool for occupied and occupied standby ventila-
tion.
The controller can also receive a communicated outdoor air damper mini-
mum position setpoint. A communicated minimum position setpoint has
priority over all configured minimum position setpoints. When a commu-
nicated minimum position setpoint is not present, the controller uses the
configured minimum setpoints (see Table 20 on page 56).
Table 20. Determining the outdoor air damper minimum position
setpoint
Occupancy
communicated value
Unoccupied Present or not present
Present
Occupied
Not present
Present
Occupied bypass
Not present
Present
Occupied standby
Not present
Hydronic heating valve
Modulated to maintain
desired setpoint
100% open
nviOAMinPos Active outdoor air damper
minimum position setpoint
Zero
Communicated value
Occupied minimum
Communicated value
Occupied minimum
Communicated value
Occupied standby minimum
Face-and-bypass
damper
Full coil face (operation
disabled)
Modulated to maintain
desired setpoint
(operation enabled)
CNT-SVX05B-EN