Trane Horizon OAKD Series Installation, Operation And Maintenance Manual page 66

Alarms and Troubleshooting
Table 19. TOAU UC600 alarms
Point Diagnostic Possible Cause
VFD not operating
Outdoor and/or Return Air Dampers not
Operating Properly
Indoor Fan Motor Failure
Indoor Fan
1
Indoor Fan Failure Switch IFFS (pressure)
Failure
Failure
IFFS Tubing damaged or not properly
connected
Refer to startup procedure
No voltage at actuator
Failed OAD power transformer
OAD Proving
No continuity thru end switch (check at UC)
3
Switch
Note: If unit optional RA damper is
installed, send switch on OAD is always
proven
BAS communication down
Discharge Air
6 Temp Source
Failed sensor or improper sensor
Failure
installation
8 Fire Shutdown BAS ONLY
Heat Overridden OFF
Compressor(s) Overridden ON
Low Temp Setpoint Failures Incorrect
10
Lockout
DAT sensor malfunction
Reference
issues
BAS communication down
Space Temp
11
Failed sensor or improper sensor
Source Failure
installation
BAS communication down
OA Temp Source
13
Failed sensor or improper sensor
Failure
installation
BAS communication down
OA Humidity Failed sensor or improper sensor
14
Source Failure installation
Humidity Wiring is polarity sensitive
Heat Overridden ON
Low discharge air volume
Dirty air filters
High Temp High gas heater manifold pressure
15
Lockout
OA/RA damper position incorrect
High temp limit not properly installed or
wired
DAT sensor malfunction
Check all Alarms
17 System Lockout
External safety device failed open
BAS communication down
Space RH Source Failed sensor or improper sensor
19
Failure installation
Humidity Wiring is polarity sensitive
Failed RH or temperature sensor
ERV Leaving Air
32
Incorrectly installed or connect RH or Temp
Condition Failure
sensor
66
Table 20, p. 66 for heat failure
Table 19. TOAU UC600 alarms (continued)
Point Diagnostic Possible Cause
Applies to 5:1 and 10:1 Gas Heaters Only
Trips after heat command "ON" and no GV
status offer 1 minute
Refer to unit "Service Facts" heat control
LED status legend
No gas, low gas pressure or high gas
42 Heat Failure
pressure to unit
Unit Manual shutoffs closed
Heater inducer failure
Heat relay failure
Loose or incorrect wiring
Table 20. TOAU UC600 troubleshooting
Trouble Possible Cause
No power supply to unit disconnect switch
Power disconnect tripped
Lockout alarm mode
Unit Not Running
Emergency Stop condition exists
Unit in Unoccupied mode
Discharge air sensor failed or not installed and
connected to unit
No gas supply to unit
Unit manual gas valve(s) closed
Heater high limit tripped
Heat relay not energized
Conditions do not warrant call for heat
No Heat
Heater control module malfunction
Roll out switch trip
Main gas on-off switch OFF
Inducer fan failure
Heater air proving switch not making or failed
Compressor limit switch(es) open
Compressor relay not energized or failed
No Compressor
Conditions do not warrant call for cooling or
dehumidification
Discharge air sensor position must be at least
4 ft.-0 in. away from unit outlet
Wide Discharge
Temp Swings
Min and Max gas heater manifold pressures not set
correctly
Setpoints not adjusted properly
Space too Hot,
Space sensors not correctly located or wired
Cold or Humid
Malfunctioning space sensor
Overcurrent alarm requires max Hz setting on VFD
IFM or PEX VFD OC
be checked and set to not exceed motor
Trip
nameplate amps
If supplied with RA pressure transducer and
EX VFD only run to
modulating damper setup is not installed or
Min HZ Setting
properly wired.
ERV leaving air temp below 34°F low temp cutout
ERV Will Not Run
Interlocked with Exhaust fan if exhaust is not
running ERV will be OFF
OAU-SVX01H-EN