Rinnai Error Codes

Rinnai Error Code 2

No Burner Operation During Freeze Protection Mode

Rinnai Error Code 3

Power Interruption During Bath Fill (Water will not flow when power returns).

Check this first

• Turn off all hot water taps. Press ON/OFF twice.

Rinnai Error Code 5

By-Pass Flow Control

Leave to a technician

• Measure resistance values of the by-pass flow control.
• Replace By-Pass flow control device.

Rinnai Error Code 10

Air Supply or Exhaust Blockage

Check this first

• Check that nothing is blocking the flue inlet or exhaust.
• Check all vent components for proper connections.

Leave to a technician

• Ensure approved venting materials are being used.
• Ensure vent length is within limits.
• Verify dip switches are set properly.
• Check fan for blockage.

Rinnai Error Code 11

No Ignition (Heating Not Turning On)

Check this first

• Check that the gas is turned on at the water heater, gas meter, or cylinder.
• If the system is propane, make sure that gas is in the tank.
• Ensure appliance is properly grounded.

Leave to a technician

• Ensure gas type and pressure is correct.
• Ensure gas line, meter, and/or regulator is sized properly.
• Bleed all air from gas lines.
• Verify dip switches are set properly.
• Disconnect EZConnect™ or MSA controls to isolate the problem.
• Ensure igniter is operational.
• Check igniter wiring harness for damage.
• Check gas solenoid valves for open or short circuits.
• Remove burner cover and ensure all burners are properly seated.
• Remove burner plate and inspect burner surface for condensation or debris.
• Check the ground wire for the PC board.

Rinnai Error Code 12

Flame Failure - No Flame

Check this first

• Check that the gas is turned on at the water heater, gas meter, or cylinder.
• Check for obstructions in the flue outlet.
• If the system is propane, make sure that gas is in the tank.

Leave to a technician

• Ensure gas line, meter, and/or regulator is sized properly.
• Ensure gas type and pressure is correct.
• Bleed all air from gas lines.
• Ensure proper venting material was installed.
• Ensure condensation collar was installed properly.
• Ensure vent length is within limits.
• Verify dip switches are set properly.
• Ensure appliance is properly grounded.
• Disconnect keypad.
• Disconnect EZConnect™ or MSA controls to isolate the problem.
• Check power supply for loose connections.
• Check power supply for proper voltage and voltage drops.
• Ensure flame rod wire is connected.
• Check flame rod for carbon build-up.
• Disconnect and reconnect all wiring harnesses on unit and PC board.
• Check for DC shorts at components.
• Check gas solenoid valves for open or short circuits.
• Remove burner plate and inspect burner surface for condensation or debris.

Rinnai Error Code 14

Thermal Fuse has Activated

Check this first

• Check for restrictions in air flow around unit and vent terminal.

Leave to a technician

• Ensure SW 5 in DIPSW 2 is in the off position.
• Check gas type of unit and ensure it matches gas type being used.
• Check for low water flow in a circulating system causing short-cycling.
• Ensure dip switches are set to the proper position.
• Check for foreign materials in combustion chamber and/or exhaust piping.
• Check heat exchanger for cracks and/or separations.
• Check heat exchanger surface for hot spots which indicate blockage due to scale build-up. Refer to instructions in manual for flushing heat exchanger.
• Hard water must be treated to prevent scale build up or damage to the heat exchanger.
• Measure resistance of safety circuit.
• Ensure high fire and low fire manifold pressure is correct.
• Check for improper conversion of product.

Rinnai Error Code 15

Venturi Control

Leave to a technician

• Ensure the Venturi motor is operating correctly.
• Replace gas valve assembly.
• Clear diagnostic code by resetting the main power supply to the water heater.

Rinnai Error Code 16

Over Temperature Warning (Safety Shutdown Because Unit is Too Hot)

Check this first

• Check for restrictions in air flow around unit and vent terminal.
• Confirm fan motor is functioning correctly.

Leave to a technician

• 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.
• Replace the gas valve assembly.

Rinnai Error Code 17

Venturi Blockage

Leave to a technician

• Ensure Venturi isn’t blocked.
• Call Rinnai technical department.

Rinnai Error Code 19

Electrical Grounding

Leave to a technician

• Check all components for electrical short.

Rinnai Error Code 21

Data Transfer Error

Leave to a technician

• If the PCB has been replaced, ensure the data transfer process has been completed.

Rinnai Error Code 25

Condensate Pump (Accessory) Condense Trap is Full

Leave to a technician

• Confirm wire connections and harness are good.
• Ensure condensate reservoir is empty and condensate pump is operating.

Rinnai Error Code 31

Burner Sensor Error

Check this first

• Measure resistance of sensor.
• Replace sensor.

Rinnai Error Code 32

Outgoing Water Temperature Sensor Fault

Leave to a technician

• Check sensor wiring for damage.
• Measure resistance of sensor.
• Clean sensor of scale build-up.
• Replace sensor.

Rinnai Error Code 33

Heat Exchanger Outgoing Temperature Sensor Fault

Leave to a technician

• Check sensor wiring for damage.
• Measure resistance of sensor.
• Clean sensor of scale build-up.
• Replace sensor.

Rinnai Error Code 34

No Burner Operation During Freeze Protection Mode

Leave to a technician

• Check for restrictions in air flow around unit and vent terminal.
• Check sensor wiring for damage.
• Measure resistance of sensor.
• Clean sensor of scale build-up.
• Ensure fan blade is tight on motor shaft and is in good condition.
• Replace sensor.

Rinnai Error Code 38

Exhaust Thermistor CO Sensor

Leave to a technician

• Check sensor wiring for damage.
• Measure resistance of sensor.
• Clean sensor of scale build-up.
• Replace sensor.

Rinnai Error Code 41

Outside Temperature Thermistor Freeze Protection Sensor

Leave to a technician

• Check sensor wiring for damage.
• Measure resistance of sensor.
• Clean sensor of scale build-up.
• Replace sensor.

Rinnai Error Code 51

Inlet Water Temperature Thermistor (Sensor)

Leave to a technician

• Check sensor wiring for damage.
• Measure resistance of sensor.
• Clean sensor of scale build-up.
• Replace sensor.

Rinnai Error Code 52

Inlet Water Temperature Thermistor (Sensor)

Leave to a technician

• Check modulating gas solenoid valve wiring harness for loose or damaged terminals.
• Measure resistance of valve coil.

Rinnai Error Code 54

High Exhaust Gas Temperature

Leave to a technician

• Ensure Heat Exchanger fins are clean and not blocked.
• Confirm inlet water temperature is not too high.
• Clear diagnostic code by resetting the main power supply to the water heater.

Rinnai Error Code 57

Burner Overheat Bi-Metal Switch

Rinnai Error Code 58

Secondary Heat Exchanger Sensor

Leave to a technician

• 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.

Rinnai Error Code 61

Combustion Fan Motor Failure

Leave to a technician

• Ensure fan will turn freely.
• Check wiring harness to motor for damaged and/or loose connections.
• Measure resistance of motor winding.

Rinnai Error Code 63

Recirculation Low Flow Circulation Flow Rate dropped below 1.3 GPM

Leave to a technician

• Ensure bypass plug is removed and bypass filter is installed. (Crossover Mode)
• Ensure both the inlet water filter and bypass filter are clean and free of debris.
• Ensure Parameter setting are correctly set for recirculation mode.
• Ensure Pump supply voltage.
• Ensure air is removed from the recirculation line.

Rinnai Error Code 65

Water Flow Control Fault

Leave to a technician

• 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.

Rinnai Error Code 70

PC Board

Leave to a technician

• Check PC board DIP switches for correct position.
• Check the connection harness at the connection on the PC board.
• Replace PC board.

Rinnai Error Code 71

Solenoid Valve Circuit Fault

Leave to a technician

• Replace PC board.

Rinnai Error Code 72

Flame Sensing Device Fault

Leave to a technician

• Ensure flame rod is touching flame when unit fires.
• Check all wiring to flame rod for damage.
• Remove flame rod and check for carbon build-up; clean with sand paper.
• 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.

Rinnai Error Code 73

Flame Sensing Device Fault

Leave to a technician

• Check sensor wiring and PC board for damage.
• Replace sensor.

Rinnai Error Code 79

Flame Sensing Device Fault

Leave to a technician

• Water has been detected at the bottom of the unit. Turn off water supply.
• Check all plumbing internally for leakage.

Rinnai Error Code LC

Scale Build-up in Heat Exchanger (when checking maintenance code history, “00” is substituted for “LC”)

Check this first

• NOTE: The LC code is the only error code that will allow the unit to keep running. The display will alternate between the LC code and the temperature setting. The controller will continue to beep. The LC code will reset if power is turned off and then on.
• Flush heat exchanger. Refer to instructions in manual.
• Replace heat exchanger.
• LC0-LC9 indicates that there is scale build up in the heat exchanger and that the heat exchanger 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.
• To operate the water heater temporarily until the heat exchanger can be flushed, push the On/Off button on the temperature controller 5 times. Repeated LC codes will eventually lockout the water heater.

Leave to a technician

• Water has been detected at the bottom of the unit. Turn off water supply.
• Check all plumbing internally for leakage.

Rinnai Error Code SS

(SS) Service Soon (Flush Heat Exchanger)

Check this first

• SS is a time-based service indicator set during installation.
• See section “3.12 Parameter Settings” for additional details on setting and changing the SS indicator.
• SS indicates that it is time for service. The heat exchanger should be flushed to prevent damage (refer to section Flushing the Heat Exchanger for more information).
• Hard water must be treated to prevent scale build-up or damage to the heat exchanger.
• To reset the SS code, push the On/Off button on the temperature controller 5 times in 5 seconds.

Rinnai Error Code FF

Maintenance Has Been Performed

Check this first

• Indicates a licensed professional performed maintenance or corrected an issue

Rinnai Error Code NO CODE

Maintenance Has Been Performed

Check this first

• Clean inlet water supply filter.
• On new installations ensure hot and cold water lines are not reversed.
• Check for bleed over. Isolate unit from building by turning off cold water line to building.
• Isolate the circulating system if present. Open your pressure relief valve; if water is flowing, there is bleed over in your plumbing.
• Ensure you have at least the minimum flow rate required to fire unit.
• Ensure turbine spins freely.
• Measure the resistance of the water flow control sensor.
• Check for DC shorts at components.