Is Your Rinnai Tankless Water Heater Reporting Errors?
Find your code below. When the fix needs a technician, Hot Water Now repairs Rinnai tankless systems across the Denver metro.
Troubleshooting tips in RED should be done by your local professionals at Hot Water Now!
Rinnai Error Code 2
Rinnai Error Code 3
Rinnai Error Code 5
Rinnai Error Code 10
Air Supply or Exhaust Blockage
- Check that nothing is blocking the flue inlet or exhaust.
- Check all vent components for proper connections.
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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 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.
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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 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.
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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 for restrictions in air flow around unit and vent terminal.
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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
Rinnai Error Code 16
Over Temperature Warning (Safety Shutdown Because Unit is Too Hot)
- Check for restrictions in air flow around unit and vent terminal.
- Confirm fan motor is functioning correctly.
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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
Rinnai Error Code 19
Rinnai Error Code 21
Rinnai Error Code 25
Rinnai Error Code 31
Burner Sensor Error
- Measure resistance of sensor.
- Replace sensor.
Rinnai Error Code 32
Rinnai Error Code 33
Rinnai Error Code 34
No Burner Operation During Freeze Protection Mode
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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 41
Rinnai Error Code 51
Rinnai Error Code 52
Rinnai Error Code 54
High Exhaust Gas Temperature
Rinnai Error Code 57
Rinnai Error Code 58
Secondary Heat Exchanger Sensor
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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
Rinnai Error Code 63
Recirculation Low Flow Circulation Flow Rate dropped below 1.3 GPM
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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
Rinnai Error Code 71
Rinnai Error Code 72
Flame Sensing Device Fault
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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
Rinnai Error Code 79
Rinnai Error Code LC LC0, LC1, LC2 00
Scale Build-up in Heat Exchanger (when checking maintenance code history, “00” is substituted for “LC”)
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.
- For your safety and the health of your equipment, Call or Contact Hot Water Now! for further troubleshooting
- 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)
- 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
- Indicates a licensed professional performed maintenance or corrected an issue
Rinnai Error Code NO CODE
Maintenance Has Been Performed
- 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.
Get in Touch With Us
Learn more about our boiler and water heater repairs, installation, and maintenance services in Lakewood, contact our team at Hot Water Now! any time. We serve clients in:
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