FORM 100.50-NOM7 (808)
83
JOHNSON CONTROLS
6
FAULT DESCRIPTION TABLE – NOTES
1. The rooftop unit is shut down when the controller for the rooftop unit is in a dened idle state, ‘shutdown’, where all of its outputs are OFF.
2. ‘General Unit Status’ is the rst display under ‘UNIT STATUS’. When applicable, ‘Trbl’ (Trouble) and ‘Alm’ (Alarm) correlate with the
RDU’s History buer.
3. OpData’ = Operation Data display item.
4. Except as noted, every fault (a) illuminates the System Alarm LED on the display and (b) creates a related entry in the History buer.
5. Supply Fan output is set to 0 after duct pressure greater than limit for 10 seconds or less.
6. The unit shuts down EXCEPT for the hot water valve, which is driven to 100% open.
7. When commanded to turn OFF, a compressor stops operating within one second. Both compressors in the system remain OFF until the
specied ‘Reset When’ conditions are met. If any system locks out, any other available systems may operate.
8. Both compressors in the system turn OFF for at least 10 minutes. If any system turns OFF due to a trip, any other available systems may
operate.
9. All trip counters are reset to zero after a power cycle to the controller.
Counter #1 for each system: An individual trip counter resets if {(trip counter #1 > 0) AND (one or both compressors are operating in the as-
sociated system) AND (15 minutes has passed since the last trip added to trip counter #1)}.
Counter #2 for each system: An individual trip counter resets if {(trip counter #2 > 0) AND (both compressors are operating in the associated
system) AND (15 minutes has passed since the last trip added to trip counter #2)}.
10. Neither error history nor illumination of the System Alarm LED is provided for the Tstat Cooling or Heating faults.
11. ‘Press= ???’ is only displayed if the building static pressure sensor becomes unreliable after startup.
12. In CV mode, the unit shuts down and displays the fault shutdown message if the RAT sensor is not detected OR is unreliable. In VAV mode,
the unit self congures to Stand Alone mode and continues to operate, though it will shut down if the SAT sensor is not detected OR is unreli-
able.
13. This message appears if the OAT sensor is disconnected or is unreliable and if ‘Economizer Enable’ = ON.
14. If the RAT sensor becomes unreliable after operation defaulted to it due to the space temperature sensor becoming unreliable, the unit will
shut down.
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