Troubleshooting; Error Codes And Checkpoints - Noritz NR501-OD Service Manual

7. Troubleshooting

Error Codes and Checkpoints

Error Codes
Display Remote
Window Controller
11 11
121 12
Flame Rod does not detect flame
(Flame fault detection)
122
14 14
Overheat Prevention Device
(Thermal Fuse) triggered
161 16
Abnormally high output
162
temperature
163
20 20
High Limit Switch triggered
Condensate Container clogging
301 30
Thermistor - Air abnormality
302
311 31
Thermistor - Cold Water
abnormality
312
321
32
Thermistor - Hot Water
abnormality
322
323
331 33
Thermistor - Heat Exchanger
abnormality
332
351,353 35
Thermistor - Exhaust
abnormality
352,354
51 51
Failure of Gas Solenoid Valve
(or Gas Solenoid Valve drive
511
circuit abnormality)
611 61
Fan Motor abnormality
612
614
70 70
Circuit Board abnormality
Note 1)
71 71
Gas Solenoid Valve drive circuit
abnormality
Note 1) Circuit Board abnormality
72 72
Flame Rod circuit abnormality
(Detection of flame when no
flame is present)
731 73
Circuit Board setting abnormality
(Improper maintenance writers
settings)
733
Circuit Board setting abnormality
(DIP Switch settings)
Circuit Board abnormality
734
Circuit Board abnormality
768 76
Display Window transmission
abnormality
No 760
Remote Controller transmission
Display abnormality
90 90
Air flow abnormality
(Unit shuts off)
901
Combustion abnormality
(Warning indication)
Combustion abnormality
(Unit shuts off)
902
Combustion abnormality
(Unit shuts off)
903
Combustion abnormality
(Unit shuts off)
908
Combustion abnormality
(Unit is locked)
91 91
Improper gas type
941 94
Exhaust temperature is too high
942
Combustion abnormality
(Unit is locked)
C C1
Detect Scale Build-up in the Heat
Exchanger
~ ~
(Warning indication, and then
C C4
Unit shuts off)
Note 2)
CF CF
Detect Scale Build-up in the Heat
Exchanger
Note 3)
(Unit is locked)
Note 1) = 1, 2, 3, 4, 5, 6, 7, 8, 9
Note 2) = 1, 2, 3, 4
= 1, 2, 3, 4, 5, 6, 7, 8, 9, A, b, C, d, E, F
Note 3) = 1, 2, 3, 4, 5, 6, 7, 8, 9, A, b, C, d, E, F
Description Diagnosis Point (Trouble Point)
Check the gas supply piping and pressure. Check for Igniter
spark ( 13 ). Check Gas Solenoid Valves ( 14,15,18 ).
Check Flame Rod ( 10 ). Check ground, paying special attention to
the ground connection to the Circuit Board.
Check for accidental extinction of the flame. Check for abnormal
combustion. Check Gas Solenoid Valves ( 15,16,18 ). Check
Flame Rod ( 10 ). Check improper connection of earth cable.
Check for melting or damage to the Thermal Fuse ( 1 ).
Check for improper connection of Thermal Fuse.
Measure the resistance through the Thermistor-Hot Water ( 5 ).
Check for Gas Proportioning Valve ( 18 ).
Check for Manifold Pressure.
Check if High Limit Switch is triggered ( 19 ).
Check for improper connection of High Limit Switch.
Check if the drain line is clogged or frozen ( 20 ).
Measure the resistance through the Thermistor
-Air ( 8 ). Check for improper connection of
Thermistor-Air.
Measure the resistance through the Thermistor
-Cold Water ( 4 ). Check for improper
connection of Thermistor-Cold Water.
Measure the resistance through the Thermistor
-Hot Water ( 5 ). Check for improper
connection of Thermistor-Hot Water.
Measure the resistance through the Thermistor
-Heat Exchanger( 6 ). Check for improper
connection of Thermistor-Heat Exchanger.
Measure the resistance through the Thermistor
-Exhaust ( 7 ). Check for improper connection
of Thermistor-Exhaust.
Check for improper connection of the Gas Solenoid Valves.
Check for damage to the Gas Solenoid Valve connections.
Circuit Board Failure
Check that the fan is rotating and check the pulse frequency from
the fan rotational frequency sensor ( 11,12 ). Check for improper
connection of the fan. Check voltage from Circuit Board.
Circuit Board failure.
Circuit Board failure.
Circuit Board failure.
Measure the current from the Flame Rod when there is no flame
( 9 ).
Check for a ground fault.
Check for improper setting of maintenance writers on Circuit Board.
Check the DIP Switch settings.
(ex.high elevation, vent length, etc.).
Circuit Board failure.
Circuit Board failure.
Check connection from Display Window to Circuit Board.
Check Display Window and Circuit Board for damage.
Check connection from Remote Controller to Circuit Board.
Check Remote Controller and Circuit Board for damage.
Check flue and air inlet for blockage or obstruction.
Check for abnormal combustion.
Check flue and air inlet for blockage or obstruction.
Check for abnormal combustion.
Check flue and air inlet for blockage or obstruction.
Check for abnormal combustion.
Check flue and air inlet for blockage or obstruction.
Check that flame ignites all across the burner.
Check Gas Solenoid Valves ( 16,17,18 ).
Check for abnormal combustion.
Check flue and air inlet for blockage or obstruction.
Check for abnormal combustion.
Check flue and air inlet for blockage or obstruction.
Check gas type
Check for abnormal combustion ( 7 ).
Check for abnormal combustion.
Check flue for blockage or obstruction.
Flush the Heat Exchanger to remove the Scale Build-up.Refer to the "Procedure for Flushing the Heat Exchanger"
in the Parts List inside pocket of the front cover.
If the Heat Exchanger is not flushed, the unit will repeat the warning indication and then shut off.The unit is locked
before long.The unit can temporarily operate by reconnecting electrical power until the Heat Exchanger is flushed.
Please contact Noritz America for more information about flushing the Heat Exchanger.
The unit is locked because of repeated Scale Build-up error code.
Must flush the Heat Exchanger to remove the Scale Build-up.
Before flushing the Heat Exchanger, please contact Noritz America for more information.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
Check for an open
circuit.
Check for a short
circuit.
Check for an open
circuit.
Check for a short
circuit.
Check for an open
circuit.
Check for a short
circuit.
Detection tempera-
ture abnormality
Check for an open
circuit.
Check for a short
circuit.
Check for an open
circuit.
Check for a short
circuit.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, contact the nearest
NORITZ agent.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, the power needs to
be disconnected and then reconnected.
To reset this error code, contact the nearest
NORITZ agent.
28
Remarks