Rinnai REU-KA3237FFUD-US User Manual

Condensing Water Heater Service Manual 7 100000354
Code Definition Remedy
16
Over Temperature
Warning
Check for restrictions in the intake and exhaust system.
Check for low water flow in a circulating system causing short-cycling.
Check for foreign materials in combustion chamber and/or exhaust piping.
Check for blockage in the heat exchanger.
19
Electrical Grounding Check all components for electrical short.
25
Condensate Trap Error Condensate container is full.
Check condensate drain for blockage.
Replace condensate trap.
31
Burner Sensor Error Measure resistance of sensor.
Replace sensor.
32
Outgoing Water
Temperature Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Clean sensor of scale build-up.
Replace sensor.
33
Heat Exchanger Outgoing
Temperature Sensor
Check sensor wiring to be sure it has not been short circuited.
Measure resistance of sensor.
Clean sensor of scale build-up.
Replace sensor.
41
Outside Temperature
Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Clean sensor of scale build-up.
Replace sensor.
51
Inlet Water Temperature
Sensor
Check sensor wiring for damage.
Measure resistance of sensor.
Clean sensor of scale build-up.
Replace sensor.
52
Modulating Solenoid
Valve Signal Abnormal
Check modulating gas solenoid valve wiring harness for loose or damaged terminals.
Measure resistance of valve coil.
57
Burner
(Bi-Metal sensors /
Thermal Fuse Harness)
Check for continuity through bi-metal sensors located at top of heat exchanger at white plastic
connector containing red an white wires.
58
Secondary Heat
Exchanger
There is scale build-up in the secondary heat exchanger and it needs to be flushed to prevent
damage. Refer to the flushing instructions in the manual. Hard water must be treated to prevent
scale build-up or damage to the heat exchanger.
61
Combustion Fan Failure Ensure fan will turn freely.
Check wiring harness to motor for damaged and/or loose connections.
Measure resistance of motor winding.
Check for proper voltage from PC board.
65
Water Flow Control The water flow control valve has failed to close during the bath fill function. Immediately turn off
the water and discontinue the bath fill function. Contact a state qualified or licensed contractor to
service the appliance.
70
Sensor Harness
Connection
Check PC board switches (in the bank of 6 switches, #2 should be on for indoor models and off for
outdoor models on KA series units only)
Check the connection harness at the E connection on the PC board. Outdoor models should have
2 orange cables at #7 and 8 positions. Indoor models should not have cables at these positions. If
this is incorrect then replace the sensor harness.
Replace PC board
71
Solenoid Valve Circuit Replace PC board.
72
Flame Sensing Device Verify flame rod is touching flame when unit fires.
Check all wiring to flame rod.
Remove flame rod and check for carbon build-up; clean with sand paper or emery cloth.
Check inside burner chamber for any foreign material blocking flame at flame rod.
Measure micro amp output of sensor circuit with flame present.
Replace flame rod.
Diagnostic Codes

Rinnai REU-KA3237FFUD-US Specifications

General

Brand	Rinnai
Model	REU-KA3237FFUD-US
Category	Water Heater
Language	English