Rinnai RUC80i Training Program page 74

Maintenance:
31
32 Outgoing Water Thermistor Faulty
33 Heat Exchanger Outgoing Thermistor Faulty
34
Combustion Air Thermistor Faulty
38
Exhaust Gas Temperature Sensor Faulty
41 Outside Temperature Sensor Faulty
51 Inlet Water Temperature Sensor Faulty
52 Modulating Solenoid Valve Signal Abnormal
High Exhaust Gas Temperature (RUS/RUCS
54
57
58
Secondary Heat Exchanger overheat
61
63
65
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PROPRIETARY and CONFIDENTIAL
Fault Codes.
Burner Sensor
Models Only)
Burner overheat
Combustion Fan
Circulation Pump
Water Flow Servo
Enhancing Lives By Changing The Way Water Is Heated
Check sensor wiring for damage or disconnection.
–
Measure resistance of sensor.
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Clean sensor of scale build-up.
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Replace Sensor.
–
Code 38 applies to the RUS/RUCS models only
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Code 41 will allow the water heater to continue operating. Freeze protection heaters will go
–
into a default heating mode.
Code 51 will allow the water heater to continue operating but Circ-Logic will be disabled.
–
Check modulating gas solenoid wire harness for loose or damaged terminals .
–
Measure resistance of valve coil.
–
- Check for scale buildup and/or excessive heat to primary / secondary heat exchangers.
Check burner area of heat exchanger for excessive heat or heat damage.
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Check continuity through both Overheat switches #2 and associated wiring.
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Check for scale buildup or heat damage to the secondary heat exchanger.
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Check for continuity through the Overheat Switch #3 and associated wiring.
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Ensure fan will turn freely.
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Check wiring harness to motor for damaged and/or loose connections.
–
Measure resistance of motor windings.
–
Ensure isolation valves are open and inlet filter screen is not obstructed.
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Ensure unit is set up properly for the application (dedicated or crossover mode).
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Ensure dedicated return line is not blocked or has a closed valve.
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Ensure Air is purged from piping and return line.
–
- The water flow control valve has failed to close during the bath fill mode.
- Damage to the water flow control valve or wiring / no feedback signal from valve to
main circuit board.
74
(Continued on next page)
5/4/2018