135
YORK INTERNATIONAL
FORM 100.50-NOM1 (604)
8
TABLE 34 – FAULT DESCRIPTION TABLE (continued)
FAULT TITLE
RDU’s HISTORY
BUFFER
SET WHEN
RESET WHEN
SHUT
DOWN
(1)
GENERAL
STATUS
ADDITIONAL ACTIONS
or DISPLAYS
(3) (4)
TROUBLE
ALARM
SensConsist Fault
#2
During Sensor Consistency
check the SAT-(OAT+1.5F)] is
greater than 3.
During Sensor
Consistency check’ the
SAT-(RAT+1.5F)] is less
than or equal to 3 AND
RAT - Space
Temperature is less than
or equal to 3 OR Cycle
power on controller.
*
––
UNT Comm Fault
Unit programmed for refrigerant
refrigerant transducer package
OR Low Ambient Operation AND
the Primary Unit Controller loses
communication with the MOD-
UNT.
Communication between
the Primary Unit
Controller and the MOD-
UNT is restored.
*
MOD-UNT controls VSDs
to setpoint.
RA Byp Filter
Fault
Unit is programmed for VAV
FlexSys and the Bypass Filter
Switch is closed for 60 sec.
Bypass fi lter switch
opens.
*
––
NOTES (PAGES 132 - 135):
1. The rooftop unit is shut down when the controller for the rooftop unit is in a defi ned idle state, ‘shutdown’, where all of its outputs are OFF.
2. ‘General Unit Status’ is the fi rst display under ‘UNIT STATUS’. When applicable, ‘Trbl’ (Trouble) and ‘Alm’ (Alarm) correlate with the RDU’s
History buffer.
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 buffer.
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
specifi ed ‘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 confi gures 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.
15. The airfl ow sensor on Input #2 is only present when the ¼ - ¾ confi guration is installed.
16. The Bad OAF Transducer test is not run if an OAF sensor is unreliable and only tested in UNOCC mode.
TABLE 34 – FAULT DESCRIPTION TABLE – NOTES
