Trane UniTrane, Installation, Operation And Maintenance Manual

Page: 139 / 164

Diagnostics and Troubleshooting
UNT-SVX07J-EN 139
Translating Multiple Diagnostics
The controller senses and records each diagnostic
independently of other diagnostics. It is possible to have
multiple diagnostics present simultaneously. The
diagnostics are reported in the order they occur.
Possible diagnostics include:
•
Low coil temperature detection
• Condensate overflow
• Low air flow—fan status
• Discharge air temp limit
• Space temperature failure
1
• Entering water temp failure
1
• Discharge air temp failure
• Outdoor air temp failure
1
• Local setpoint failure
1
• Local fan mode failure
1
• CO
2
sensor failure
1
• Generic AIP failure
1
• Humidity input failure
1
• Defrosting compressor lockout
1
• Maintenance required
2
• Invalid Unit Configuration
2
• Generic temperature failure
2
• Discharge air low limit
Resetting Diagnostics
There are seven ways to reset unit diagnostics:
• Automatically by the controller
• By initiating a manual output test at the controller
(Tracer® ZN010, ZN510, or ZN520 only)
• By cycling power to the controller
• By using a building automation system
• By using the Rover service tool
• By using any other communicating device able to
access the controller’s diagnostic reset input (Tracer®
ZN510 or ZN520 only)
• By cycling the fan switch from off to any speed setting
(Tracer® ZN520 only)
Automatic Reset by the Controller
The controller includes an automatic diagnostic reset
function which attempts to automatically restore the unit
when a low temperature diagnostic occurs.
Note: The controller implements the automatic
diagnostic reset function only once every 24 hours.
For the controller to increment the 24-hour timer,
you must maintain power to the controller. Cycling
power resets all timers and counters.
After the controller detects the first low temperature
diagnostic, the unit waits 30 minutes before invoking the
automatic diagnostic reset function. The automatic
diagnostic reset function clears the special diagnostic and
attempts to restore the controller to normal operation. The
controller resumes normal operation until another
diagnostic occurs.
Note: The automatic diagnostic reset function does not
operate during the manual output test sequence.
If a special diagnostic occurs within 24 hours after an
automatic diagnostic reset, the controller must be
manually reset. Other possible methods of resetting
diagnostics are described in the sections that follow.
Table 76. Tracer® ZN520 test sequence
Step
Fan
Main
Valve
Electric Heat or
Aux. Valve
Fresh Air
Damper Generic/Baseboard Heat
J1-1 J1-2 J1-3 J1-5 J1-6 J1-9 J1-10 J1-11 J1-12 TB4-1
1. Off
1
Off Off Off Off
On
EH: off
Off aux: on Off On Off
2. Fan high
2
High Off Off Off Off Off Off Off Off Off
3.
3
Off Off Off Off Off Off Off Off Off
4. Fan low Off Off Low Off Off Off Off Off Off Off
5. Main open High Off Off On Off Off Off Off Off Off
6. Main close, EH1 on High Off Off Off On On Off Off Off Off
7. Aux. open High
EH1 on
Exh
4
Off Off Off On Off Off Off Off
8. Aux. close, damper open
High Off Off Off Off
Off
EH1 off
On
EH2 on
On Off Off
9. Damper close High Off Off Off Off Off Off Off On Off
10. Generic/baseboard heat
energized
High Off Off Off Off Off Off Off Off On
11. Exit
5
Exit
Notes:
1
Upon entering manual output test mode, the controller turns off all fan and electric heat outputs and drives.
2 At the beginning of Step 2 , the controller attempts to clear all diagnostics.
3
The low fan speed output energizes at Step 3 . If the unit is configured for a 1-speed fan, the fan remains on high speed at Step 3 .
4
If the unit is configured for a 1- or 2-speed fan, and BOP2 is configured for an exhaust fan, the exhaust fan output energizes on Step 7 . The
exhaust fan output is shared with medium speed.
5 After Step 10 , the test sequence performs an exit. This initiates a reset and attempts to return the controller to normal operation.
1
Non-latching diagnostics automatically reset when the input is present and valid.
2
Does not apply to the Tracer
®
UC400-B controller.