Trane Rtaaiom3 Manual

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
NONE Outdoor Air Temperature None All Open or Short
Sensor (Both Outdoor Air a. Display dashes e.g. 14 - - - - -”,
Reset or Low Ambient Lockout
Not Selected)
Ab Evap. Leaving Water Temp. Sensor MMR All Open or Short
bA Overload Trip - Compressor A CMR Compressor  Energized Compressor current exceeded overload
time vs. trip characteristic.
bb Overload Trip - Compressor B CMR Compressor  Energized Compressor current exceeded overload
time vs. trip characteristic.
bC Overload Trip - Compressor C CMR Compressor  Energized Compressor current exceeded overload
time vs. trip characteristic.
bd Overload Trip - Compressor D CMR Compressor  Energized Compressor current exceeded overload
time vs. trip characteristic.
bE High Pressure Cutout - Compressor C CMR All a. A high pressure cutout was detected on
Compressor C; trip at 405 + or - 7 PSIG.
BF  High Pressure Cutout - Compressor D CMR All a. A high pressure cutout was detected on
Compressor D; trip at 405 + or - 7 PSIG.
NONE CWS/Leaving Water Temp. None All No diagnostic, display to flash and
Cutout Setpoint Overlap limit value to last legal value.
NOTE: The above is not a diagnostic because you don’t want the display vectoring you to a different display state when you
are trying to set either the chilled water setpoint or the leaving water temp. cutout setpoint as it will in the case of a diagnostic.
C5 Low Chilled Water Temperature IFW No Circuits Energized a. The chilled water temp. fell below
(Unit Off) the cutout setpoint while the
compressors were not running.
C6 Low Chilled Water Temperature MAR Any Circuit Energized a. The chilled water temp. fell below
(Unit On) the cutout setpoint while the
compressors were running for 30 F - sec.
CA Contactor - Compressor A MMR Compressor a. Welded compressor contactor.
Not Energized b. Detected a welded compressor contactor
off but the current does not go to zero.
Detection time shall be 5 second
minimum and 10 seconds maximum.
On detection, generate the diagnostic,
energize the appropriate alarm relay,
continue to command the affected
compressor off, energize the affected
compressors oil line solenoid, stop all
other compressors, unload the running
compressor with the welded contactor,
open the EXV to it’s maximum open
position, and continue to do fan control.
Do not exit this condition until the
controller is manually reset.
Cb Contactor - Compressor B MMR Same as CA Same as diagnostic CA
CC Contactor - Compressor C MMR Same as CA Same as diagnostic CA
Cd Contactor - Compressor D MMR Same as CA Same as diagnostic CA
d7 Over Voltage MAR  Pre-start and a. Line voltage above +10% of nominal.
Any  Circuit(s) (Must hold = +10% of nominal.
Energized Must trip = +15% of nominal.) 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
d8 Under Voltage MAR Pre-start and a. Line voltage below -10% of nominal
Any Circuit(s) Energized the Under/Over transformer is not
connected. (Must hold = -10% of
nominal Must trip = -15% of nominal).
Ed Chilled Water Flow Interlock MAR All Modes Except a. The chilled water flow switch input
STOP (00) and was open for more than 6 seconds.
EXTERNAL STOP (100)
F5 High Pressure Cutout - CMR All a. A high pressure cutout was detected
Compressor  A on Compressor A; trip at 405 + or
- 7 PSIG.
F6 High Pressure Cutout - CMR All a. A high pressure cutout was detected
Compressor  B on Compressor B; trip at 405 + or
 - 7 PSIG.
Fd Emergency Stop MMR All a. EMERGENCY STOP input is open.
An external interlock has tripped.
Time to trip from input opening to unit
stop shall be 0.1 to 1.0 sec.
180 Starter  Transition CMR a. The UCM did not receive a
Compressor A transition complete signal in the
designated time from the UCM
command to transition. The must
hold time from the UCM transition
command is 1 second. The Must trip
time from the transition time is 6
seconds.
b. The Transition Complete input was
found to be shorted before the
compressor was started.
c. Active only if Reduced Inrush
Starting is enabled.
181 Starter Transition - Compressor B CMR Same as 180 Same as diagnostic 180.
182 Starter Transition - Compressor C CMR Same as 180 Same as diagnostic 180.
183 Starter Transition - Compressor D CMR Same as 180 Same as diagnostic 180.
184 Phase Reversal - Compressor A CMR a. A phase reversal was detected on
the incoming current. On a
compressor start-up the phase
reversal logic must detect and trip in a
maximum of 1.0 second from
compressor start.
185  Phase Reversal - Compressor B CMR Same as diagnostic 184.
186 Phase Reversal - Compressor C CMR Same as diagnostic 184.
187 Phase Reversal CMR Same as diagnostic 184.
Compressor D 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
190 Low Superheat Circuit 1 CMR All Running Modes a. A low superheat condition existed
for an extended period of time. If a
superheat less than or equal to 2 F is
detected for more than 2400 F
seconds, the circuit shall be shut
down. The integrated area (2400 F
seconds) shall be only below 2 F
superheat.
191 Low Superheat - Circuit 2 CMR All Running Modes Same as diagnostic 190.
194 Low Evap. Rfgt. Temp. -  Circuit 1 CMR Compressor  Energized a. The Saturated Evaporator Refrigerant
Temp.- Circuit 1 dropped below the
Low Refrigerant Temp. Cutout Setpoint
when the circuit was running for
30 F seconds.
b. See the low ambient ignore time on
start-up.
195 Low Evap. Rfgt. Temp. CMR Compressor  Energized Same as diagnostic 194, but for Ckt 2.
198 Low Oil Flow - Compressor A CMR Compressor  Energized a. The differential oil pressure switch
 remained open for more than
 20 contiguous seconds on
 Compressor A.
199 Low Oil Flow - Compressor B CMR Compressor  Energized Same as diagnostic 198, but for Cprsr B.
19A Low Oil Flow - Compressor C CMR Compressor  Energized Same as diagnostic 198, but for Cprsr C.
19b Low Oil Flow - Compressor D CMR Compressor  Energized Same as diagnostic 198, but for Cprsr D.
19C Phase Loss Compressor A CMR Compressor  Energized a. No current was sensed on one or more
of the current transformer inputs. (Must
hold = 20% RLA. Must trip = 5% RLA.)
Time to trip shall be I second minimum
and 3 seconds maximum.
19d Phase Loss Compressor B CMR Same as 19C Same as diagnostics 19C
19E Phase Loss Compressor C CMR Same as 19C Same as diagnostics 19C
19F Phase Loss Compressor D CMR Same as 19C Same as diagnostics 19C
1A0 Power Loss Compressor A CAR All Running Modes a. The compressor was running and all
three phases of current were lost.
b. There was an open Transition input
after transition had been previously
proven to have been complete.
c. There was an incomplete Transition on
the first check after transition and all
three phases of current here not
present.
1A1 Power Loss - Compressor B CAR Same as 1A0 Same as diagnostic 1A0.
1A2 Power Loss - Compressor C CAR Same as 1A0 Same as diagnostic 1A0.
1A3 Power Loss - Compressor D CAR Same as 1A0 Same as diagnostic 1A0. 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
1A4 Remote Communications Loss IFW All AUTO/REMOTE Modes a. While the chiller switch was in the
AUTO/REMOTE the communication
between the CSR and the connected
remote device, e.g. a Tracer or
Remote Display, had either never
been established for more than 15
minutes after power up or was lost for
more than 15 minutes after it had
been established; use the Front Panel
Setpoints and the Default Chiller Auto/
Stop.
All AUTO/LOCAL and all b. In AUTO/LOCAL communications had
STOP/RESET  modes been established and was then lost for
more than 15 minutes. Regardless of
the remote communication status the
UCM uses Front Panel setpoints.
NOTE: The active modes for diagnostic 1A4 follows the positions of the chiller switch which account for other chiller codes.
1A5 Oil Flow Control - Compressor A CMR Pre-Stop a. At the time the 20 second Run:
Unload time times out, the UCM will
de-energize the oil line solenoid and
set a 10+ or -1 second timer. As soon
as the differential pressure switch
opens (0.8 to 1.2 sec.) the compressor
will be de-energized and the sequence
ended. If the differential pressure
switch does not open within 10
seconds, the compressor shall be de-
energized and a CMR diagnostic
generated not permitting the
compressor to restart. Whenever the
fan control pressure differential is
below 70 PSID, or if a diagnostic
shutdown occurs, the above
shutdown test will not be executed.
The above test will serve to check the
differential pressure switch, the switch
wiring to the UCM, and closure of the
oil line solenoid.
1A6 Oil Flow Control - CMR Pre-Stop Same as diagnostic 1A5. Compressor B
1A7 Oil Flow Control - CMR Pre-Stop Same as diagnostic 1A5. Compressor C
1A8 Oil Flow Control - CMR Pre-Stop Same as diagnostic 1A5. Compressor D
1A9 EXV Electrical Drive Circuit CMR Pre-Start and On Demand a. Wiring between the EXV and the UCM
(Rfgt. Circuit 1) is “Open”. Check the connector for
proper termination.
b. EXV motor is faulty.
c. EXV drive circuits on Module 1U3 are
faulty.
1AA EXV Electrical Drive Circuit CMR Pre-Start and On Demand Same as diagnostic 1A9.
(Rfgt. Circuit 2)
NOTE: For similar diagnostics for the Slaved EXV Drive Circuits see Codes 1 db and 1 dC. 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
1Ad  Memory Error Type I  IFW UCM Power Up or a. On UCM power up or following a
Following a Type II Type II Memory Error a NOVRAM
Memory Error memory error was detected. The UCM
is operating on all Engineering ROM
defaults for all setup parameters.
Check all I setup parameters and
continue to run chiller. Replace the
Chiller Module as soon as a
replacement is available.
1AE Low Diff. Pressure - Circuit 1 CMR Compressor  Energized a. The fan control algorithm detected a
low differential temperature/ pressure
condition that existed for more than
180 contiguous seconds. The trip-
point is 40 PSID.
1AF Low Diff. Pressure - Circuit 2 CMR Compressor  Energized Same as diagnostic 1AE.
1b2 Severe Phase Unbalance - CMR All Running Modes a. A 30% Phase Unbalance diagnostic
Compressor A has been detected. The 15% Phase
Unbalance criteria has been defeated.
Items to check are the Current
Transformer Part Numbers (they
should all match), The Current
Transformer resistances, line voltage
phase balance, all power wiring
connections, the contactor pole faces,
and the motor.
1b3 Severe Phase Unbalance - CMR All Running Modes Same as diagnostic 1b2.
Compressor B
1b4 Severe Phase Unbalance - CMR All Running Modes Same as diagnostic 1b2.
Compressor C
1b5 Severe Phase Unbalance - CMR All Running Modes Same as diagnostic 1b2.
Compressor D
1b6 Overload Setting - IFW All a. The CPM NovRam Based overload
Compressor A setting did not agree with the MCSP
Dip Switch overload setting for 30
contiguous seconds. The affected
MCSP shall use the minimum (00000
binary, 00 decimal) overload setting as
a default until the UCM is reset when
this diagnostic occurs.
1b8 Overload Setting - IFW All Same as diagnostic 1b6.
Compressor C
1b9 Overload Setting - IFW All Same as diagnostic 1b6.
Compressor D
1bA Phase Unbalance - CMR All Running Modes a. A 15% phase unbalance has been
Compressor A detected. Menu Item “47” is enabled.
1bb Phase Unbalance - CMR All Running Modes Same as diagnostic 1bA.
Compressor B
1bC Phase Unbalance - CMR All Running Modes Same as diagnostic 1bA.
Compressor C
1bd Phase Unbalance - CMR All Running Modes Same as diagnostic 1bA.
Compressor D 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
1bE Winding Temp.- Compressor A CMR All a. The motor winding temperature
 thermostat opened; nominally 221 F.
b. The motor temperature thermostat or
 wiring is open.
c.  Time to trip from input open to
 compressor shutdown shall be 0.5 to
 2.0 seconds.
1bF Winding Temp.- Compressor B CMR All Same as diagnostic 1bE.
1C0 Winding Temp.- Compressor C CMR All Same as diagnostic 1bE.
1C1 Winding Temp.- Compressor D CMR All Same as diagnostic 1bE.
1C2 Discharge Temp.- Compressor A CMR All a. The discharge temperature exceeded
 the trip value of 275 F.
b. The discharge temperature PTC or
 wiring is open.
Note: on units built in 1992 and later,
the discharge temp sensor will not be
present.
1C3 Discharge Temp. - Compressor B CMR All Same as diagnostic 1C2.
1C4 Discharge Temp. - Compressor C CMR All Same as diagnostic 1C2.
IC5 Discharge Temp. - Compressor D CMR All Same as diagnostic 1C2.
1C6 High Diff. Pressure - Circuit 1  CMR Compressor  Energized a. The difference between the condenser
pressure and the evaporator pressure
exceeded 350 PSID for 0.8 to 5.0
seconds. 320 PSID must hold, 320+ to
trip for 1 hour.
1C7 High Diff. Pressure - Circuit 2 CMR Compressor  Energized Same as diagnostic 1C6.
1d1  Memory Error Type II IFW All a. A Shadow RAM memory error was
detected. The UCM is operating on all
last valid values (pulled from
NOVRAM) for all setup parameters.
No setup parameter changes were
pending to be loaded into NOVRAM, a
complete recovery of all setup
parameters was made and there is no
need to check unit setup parameters.
Compressor starts and hours were lost
for not more than the last 24 hours.
This is expected to be an isolated
event and repair or replacement is not
required.
1d2 Memory Error Type III IFW All a. A Shadow RAM memory error was
detected. The UCM is operating on all
last valid values (pulled from
NOVRAM) for all setup parameters.
Setup parameter changes less than 24
hours old pending to be loaded into
NOVRAM were lost. Check all setup
parameters made in last 24 hours.
Compressor starts and hours were lost
for not more than 24 hours. This is
expected to be an isolated event and
repair or replacement is not required. 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
1d3 Comp. Suction Temp. Sensor - CMR All a . Open or Short in sensor electrical
Circuit 1  circuitry.
1d4 Comp. Suction Temp. Sensor - CMR All a. Open or Short in sensor electrical
Circuit 2 circuitry.
1d7 Phase Reversal Protection Lost - CMR Compressor Energized to a. The phase reversal protection
Compressor A To Transition Command Compressor A has become
inoperative. The phase rotation
protection system failed to detect two
in a row of one of the four phase
circuit states; Phase reversal, Phase
Rotation OK, Phase A lost, Phase B
lost.
1d8 Phase Reversal Protection Lost - CMR Compressor Energized to Same as diagnostic 1d7.
Compressor B Transition Command
1d9 Phase Reversal Protection Lost - CMR Compressor Energized to Same as diagnostic 1d7.
Compressor C Transition Command
1dA Phase Reversal Protection Lost - CMR Compressor Energized to Same as diagnostic 1d7.
Compressor D Transition Command
1db Slaved EXV Elec. Drive Circuit - CMR On Demand and a. Wiring between the EXV and the UCM
Refrigerant Circuit I Pre-Start  is “Open”. Check the
connector for proper termination.
b. EXV motor is faulty.
c. EXV drive circuits on Module 1U3 are
faulty
1dC Slaved EXV Elec. Drive Circuit CMR On Demand and Same as diagnostic 1db. Also refer to
Refrigerant Circuit 2 Pre-Start diagnostics 1A9 and 1AA.
412 1U1 Indicating IFW All The 1U1 Module has detected a loss of
1U2 Communications inter-processor communications from
the 1U2 Module.
413 1U1 Indicating MMR All The 1U1 Module has detected a loss of
1U3 Communications inter-processor communications from
the 1U3 Module.
414 1U1 Indicating CMR All The 1U1 Module has detected a loss of
1U4 Communications inter-processor communications from
the 1U4 Module.
415 1U1 Indicating CMR All The 1U1 Module has detected a loss of
1U5 Communications inter-processor communications from
the 1U5 Module.
416 1U1 Indicating CMR All The 1U1 Module has detected a loss of
1U6 Communications inter-processor communications from
the 1U6 Module.
417 1U1 Indicating CMR All The 1U1 Module has detected a loss of
1U7 Communications inter-processor communications from
the 1U7 Module.
418 1U1 Indicating CMR All The 1U1 Module has detected a loss of
1U8 Communications inter-processor communications from
the 1U8 Module.
431 1U3 Indicating MMR All The 1U3 Module has detected a loss of
1U1 Communications inter-processor communications from
the 1U1 Module.
434 1U3 Indicating CMR All The 1U3 Module has detected a loss of
1U4 communications inter-processor communications from
the 1U4 Module. 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
435 1U3 Indicating CMR All The 1U3 Module has detected a loss of
1U5 Communications inter-processor communications from
the 1U5 Module.
436 1U3 Indicating CMR All The 1U3 Module has detected a loss of
1U6 Communications inter-processor communications from
the 1U6 Module.
437 1U3 Indicating CMR All The 1U3 Module has detected a loss of
1U7 Communications. inter-processor communications from
.the 1U7 Module.
441 1U4 Indicating CMR All The 1U4 Module has detected a loss of
1U1 Communications inter-processor communications from
the 1U1 Module.
443 1U4 Indicating CMR All The 1U4 Module has detected a loss of
1U3 Communications inter-processor communications from
the 1U3 Module.
445 1U4 Indicating CMR All The 1U4 Module has detected a loss of
1U5 Communications . inter-processor communications from
the 1U5 Module.
451 1U5 Indicating CMR All The 1U5 Module has detected a loss of
1U1 Communications inter-processor communications from
the 1U1 Module.
453 1U5 Indicating CMR All The 1U5 Module has detected a loss of
1U3 Communications inter-processor communications from
the 1U3 Module.
454 1U5 Indicating CMR All The 1U5 Module has detected a loss of
1U4 Communications inter-processor communications from
the 1U4 Module.
461 1U6 Indicating CMR All The 1U6 Module has detected a loss of
1U1 Communications inter-processor communications from
the 1U1 Module.
463 1U6 Indicating CMR All The 1U6 Module has detected a loss of
1U3 Communications inter-processor communications from
the 1U3 Module.
467 1U6 Indicating CMR All The 1U6 Module has detected a loss of
1U7 Communications inter-processor communications from
the 1U7 Module.
471 1U7 Indicating CMR All The 1U7 Module has detected a loss of
1U1 Communications inter-processor communications from
the 1U1 Module.
473 1U7 Indicating CMR All The 1U7 Module has detected a loss of
1U3 Communications inter-processor communications from
the 1U3 Module.
476 1U7 Indicating CMR All The 1U7 Module has detected a loss of
1U6 Communications inter-processor communications from
the 1U6 Module. 
						

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Table 18
Diagnostics and Troubleshooting Chart (Continued)
DIAG. ACTIVE
CODE DIAGNOSTIC DESCRIPTION TYPE MODES CAUSE
481 1U8 Indicating MMR All The 1U8 Module has detected a loss of
1U1 Communications inter-processor communications from
the 1U1 Module.
483 1U8 Indicating CMR* All The 1U8 Module has detected a loss of
1U3 Communications inter-processor communications from
the 1U3 Module.
484 1U8 Indicating CMR All The 1U8 Module has detected a loss of
1U4 Communications inter-processor communications from
the 1U4 Module.
485 1U8 Indicating CMR All The 1U8 Module has detected a loss of
1U5 Communications inter-processor communications from
the 1U5 Module.
486 1U8 Indicating CMR All The 1U8 Module has detected a loss of
1U6 Communications inter-processor communications from
the 1U6 Module.
487 1U8 Indicating CMR All The 1U8 Module has detected a Ioss of
1U7 Communications inter-processor communications from
the 1U7 Module.
*In the event of this communication diagnostic, CMR(s) will be generated for the circuit(s) which are using the Slaved EXV
(i.e. those circuits which are employing a parallel valve arrangement). 
						

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