54
CNT-SVX07D-EN
Troubleshooting
No power to the
controller
If the controller does not have power, the outdoor air damper does not operate. For the
Tracer ZN521 controller to operate normally, you must apply an input voltage of 24 Vac. If
the green LED is off continuously, the controller does not have sufficient power or has
failed.
Diagnostic present
Several diagnostics affect outdoor air damper operation. For information about these
diagnostics, see
.
Normal
operation
The controller opens and closes the outdoor air damper based on the controller’s occu-
pancy mode and fan status. Normally, the outdoor air damper is open during occupied
mode when the fan is running and closed during unoccupied mode.
Unit configuration
The controller must be properly configured based on the actual installed end devices and
application. If the unit configuration does not match the actual end device, the outdoor air
damper may not work correctly.
Manual output test
The controller includes a manual output test sequence you can use to verify output oper-
ation and associated output wiring. However, based on the current step in the test
sequence, the outdoor air damper may not be open. Refer to the
Warm-up and cool-
down sequence
The controller includes both a morning warm-up and cool-down sequence to keep the
outdoor air damper closed during the transition from unoccupied to occupied. This is an
attempt to bring the space under control as quickly as possible.
Requested mode off
You can communicate a desired operating mode (such as off, heat, or cool) to the control-
ler. If off is communicated to the controller, the unit closes the outdoor air damper.
Table 22. Outdoor air damper remains open
Probable cause
Explanation
Unit wiring
The wiring between the controller outputs and the outdoor air damper must be present
and correct for normal outdoor air damper operation. Refer to applicable wiring diagram.
Failed end device
Check damper actuator to ensure proper operation.
Normal
operation
The controller opens and closes the outdoor air damper based on the controller’s occu-
pancy mode and fan status. Normally, the outdoor air damper is open during occupied
mode when the fan is running and closed during unoccupied mode. (See
outdoor/return air dampers,” p. 37
Unit
configuration
The controller must be properly configured based on the actual installed end devices and
application. If the unit configuration does not match the actual end device, the outdoor air
damper may not work correctly.
Manual output test
The controller includes a manual output test sequence you can use to verify output oper-
ation and associated output wiring. However, based on the current step in the test
sequence, the outdoor air damper may be open. Refer to the
.
Table 21. Outdoor air damper remains closed (continued)
Probable cause
Explanation
Содержание Tracer ZN521
Страница 59: ......