30 Rinnai aircon error codes + troubleshooting

If you have a Rinnai air conditioner, you will have an idea that it is one of the best ACs currently in the whole world market. They are reliable, durable, and don’t get into issues very often. However, if you are facing some error code on the Rinnai AC, it is not a big deal as this directly indicates a specific issue in your system.

In this article, we have gathered all the error codes that can occur on Rinnai aircon along with their causes and solutions. All you need is to look at the causes and implement solutions that seem applicable. Always seek assistance from an HVAC engineer or technician if you are not much familiar with electronics because tweaking without proper knowledge can put the health of you and your system at risk.

Rinnai air conditioner error code 2, 3

Causes:

This error is reported by the AC unit when/if:

1. The system is under freeze protection mode.
2. The no-burner operation is going on while the system is in freeze protection mode.

Solutions:

1. In most cases, the error will be down once the icing on the coils has been melted.
2. Turn OFF all the hot water taps by pressing the ON/OFF button twice on the system.
3. If the error persists, seek assistance from an HVAC engineer for inspection and further suitable procedures.

Rinnai air conditioner error code 5

Causes:

This error is displayed on the AC unit when/if:

1. The bypass flow control has been activated in the system.
2. The resistance values of the bypass flow control are wrong.
3. The bypass flow control device is malfunctioning.

Solutions:

1. Measure the resistance values of the bypass flow control and if it is wrong, seek professional help to bring it to normal.
2. Inspect the wiring and connections between the main PCB, power supply, and bypass flow control. Repair the damaged wires or loose connectors.
3. Inspect the main PCB and replace it if it is malfunctioning.
4. Check the by-pass flow control device and if it is defective, replace it.

Rinnai air conditioner error code 10

Causes:

This error is reported by the AC unit when/if:

1. The air supply is clogged due to dirt or some foreign items stuck in it.
2. The exhaust or exhaust passage of the system has blockages.

Solutions:

1. Clean the inlet or exhaust to remove dirt, dust, or any other thing causing a block.
2. Look through the vents and related components and ensure they are properly connected and tightened.
3. Measure the vents’ length and ensure it is within the limits.
4. Check the DIP (Dual In-line Package) switch and ensure they are properly installed. Repair or replace the switches as needed.
5. Inspect the fan for any blockages. Clean the fan blades and components.
6. Seek professional help to check and ensure that the right and approved venting material is being used for airflow and exhaust in your system. Replace the components as needed.

Rinnai air conditioner error code 11

Causes:

This error is triggered on the unit when/if:

1. Ignition is not happening.
2. The heating mode is not turning ON.

Solutions:

1. Using the remote controller, make sure that the gas is turned ON on the gas meter or cylinder.
2. Repair any damaged wire harness of the ignitor and the main PCB.
3. Measure the gas level and ensure it is just as required.
4. Check and ensure that the unit is grounded.
5. Clean the gas pipelines and ensure there is no air or something stuck in them.
6. Check the DIP switches for any malfunction. Repair or replace them as needed.
7. Inspect the main PCB for any defects. Replace the PCB if it’s malfunctioning.

Rinnai air conditioner error code 14

Causes:

This error is reported by the unit when/if:

1. The thermal fuse has been activated.
2. The temperature in the unit is abnormal.

Solutions:

1. Ensure proper flow of outside air to the system for keeping it cool.
2. Check the gas type in the unit and ensure it is compatible and enough for the operation.
3. Check the DIP switch and repair them if they are malfunctioning.
4. Clean the exhaust, heat exchanger, and combustion chamber to remove dirt or some foreign materials.
5. Check the resistance of the safety circuit and repair it if it is wrong.

Rinnai air conditioner error code 15

Causes:

This error is triggered on the unit when/if:

1. The venturi control has been activated.
2. The venturi motor is malfunctioning.

Solutions:

1. Check the venturi motor for malfunctioning. Repair or replace the motor if defective.
2. Check the wire harness of the venturi motor. Repair damaged wires where needed.
3. Check the gas valve and ensure it is properly installed in its intended position.

Rinnai air conditioner error code 16

Causes:

This error is displayed on the AC unit when/if:

1. The temperature is exceeding the normal limit in the system.
2. The system is shutting down because the unit is getting too hot.

Solutions:

1. Clean the evaporator, blower, vent terminals, ducts, exhaust, combustion chamber, and condensing coils for dirt and debris cover.
2. Run the fan at full speed for some time or until the temperature comes to normal.
3. Remove any restrictions causing fan blade blockages. Repair or replace the fan motor if it is faulty.
4. Check the refrigerant or gas valves and ensure they are in place. Clean or replace the valves if they are blocked or broken.

Rinnai air conditioner error code 17

Causes:

This error is reported by the unit when/if:

1. The venturi motor is blocked mostly because of dirt build-up.

Solutions:

1. Clean the motor to remove all dirt or small items stuck in it. Seek professional help by contacting the Rinnai technical department to open and reinstall the motor.

Rinnai air conditioner error code 19

Causes:

This error is triggered on the AC unit when/if:

1. There are some short circuits in any part of the system.
2. The electrical grounding of the system is not properly placed or is malfunctioning.

Solutions:

1. Seek professional help to check the electrical grounding and ensure the system is thoroughly grounded.
2. Check for short circuits. Repair the affected components as needed.
3. Check the wiring between different components for damage. Repair burned wire as needed.

Rinnai air conditioner error code 21

Causes:

This error is displayed on the AC unit when/if:

1. The communication between indoor and outdoor units or different components within one unit is interrupted.
2. The data transfer failed because of a broken transmission path.

Solutions:

1. Resend the instruction or data that first failed to transfer.
2. Check the communication wire between components and units. Repair the damaged wire or if the connectors are loose.
3. Check the main PCBs and replace either of the PCBs if it is malfunctioning.

Rinnai air conditioner error code 25

Causes:

This error is reported by the AC unit when/if:

1. The condenser or condensate pump of the system is malfunctioning.

Solutions:

1. Check the wires and connectors of the condenser for any damages. Repair damaged wires and loose connectors where needed.
2. Check the condensate reservoir and water overflow tray. Empty it if it is full.
3. Check the condenser or the condensate pump for malfunctioning. Repair or replace it as needed.

Rinnai air conditioner error code 31

Causes:

This error is triggered on the unit when/if:

1. The sensor on the burner is not working.
2. The sensor wire harness is defective.
3. The sensor has an open or short circuit.

Solutions:

1. Measure the resistance of the sensor and if it is weak or not compatible with the system, replace the sensor with a strong one.
2. Clean the sensor of scale build-up and wipe off the dirt or dust that was covering the sensor.
3. Check the wiring of the sensor. Repair any damaged wire between the sensor and the main PCB.
4. Inspect the sensor and if it is defective, replace it.

Rinnai air conditioner error code 32

Causes:

This error is displayed on the unit when/if:

1. The outgoing water temperature sensor has an issue.
2. The sensor has an open or short circuit.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 33

Causes:

This error is reported by the AC unit when/if:

1. The outgoing heat exchanger temperature sensor is malfunctioning.
2. The sensor has an open or short circuit due to unstable voltages.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 34

Causes:

This error is triggered on the unit when/if:

1. The air temperature sensor equipped on the combustion chamber is defective.
2. The wire harness is defective or the sensor has a short circuit.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 38

Causes:

This error is displayed on the AC unit when/if:

1. The exhaust thermistor sensor is malfunctioning.
2. The wire harness of the sensor is defective.
3. The sensor has an open or short circuit.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 41

Causes:

This error is reported by the AC unit when/if:

1. The temperature sensor of the system is malfunctioning.
2. The outdoor temperature thermostat freeze protection sensor is defective.
3. There is an open or short circuit in either of the sensors.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 51

Causes:

This error is triggered on the AC unit when/if:

1. The indoor unit water temperature sensor is malfunctioning.
2. The sensor has an open or short circuit.
3. The wire harness is damaged or broken.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 52

Causes:

This error is displayed on the unit when/if:

1. The inlet or incoming water temperature sensor is malfunctioning.
2. The sensor has an open or short circuit.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 54

Causes:

This error is reported by the unit when/if:

1. The gas temperature in the exhaust or piping is exceeding the normal or safe limit.

Solutions:

1. Clean the heat exchanger and its fins to remove dirt build-up covering the fins.
2. Ensure that the inlet water temperature is not high and is in the normal range.

Rinnai air conditioner error code 57

Causes:

This error is triggered on the unit when/if:

1. The burner of the system is overheating.

Solutions:

1. Check the bi-metal switch and if it is malfunctioning, seek professional help for repair.

Always contact the Rinnai technical support department for this error because the burner can overheat due to many reasons. It is better to let the technician inspect the whole system before you start using it again.

Rinnai air conditioner error code 58

Causes:

This error is displayed on the AC unit when/if:

1. The secondary sensor on the heat exchanger is not working.
2. There is an open or short circuit in the sensor.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 61

Causes:

This error is reported by the AC unit when/if:

1. The fan motor of either unit is not working.
2. The wires and connections of the fan motor are defective.

Solutions:

1. Check the fan blades and ensure they are rotating freely. Remove if something is causing a blockage.
2. Check the wires and connections between the fan motor, main PCB, and power supply. Repair wires and loose connectors if needed. 
3. Measure the resistance coefficient of the fan motor wiring. Repair the wiring or replace the fan motor (as suggested by the HVAC engineer or the technician) if it is malfunctioning.

Rinnai air conditioner error code 63

Causes:

This error is triggered on the unit when/if:

1. The recirculation or low flow circulation rate has drastically gone below the minimum range of 1.3 GPM.

Solutions:

1. Check the bypass plug and make sure it is in place and working fine.
2. Clean the inlet water filters, bypass filters, air filters, exhaust, and heat exchangers to remove dirt and debris.
3. Using the remote controller, make sure that all settings are properly set.
4. Bleed out all the air stuck in the pipes, especially the recirculation lines.

Rinnai air conditioner error code 65

Causes:

This error is displayed on the unit when/if:

1. The valve in the water flow area is not operating or failing to close.

Solutions:

1. Turn OFF the water flow and disable the bath fill process.
2. Check the valve and if it is defective, contact a professional technician or call the Rinnai technical support department for an engineer to repair the valve.

Rinnai air conditioner error code 70

Causes:

This error is reported by the AC unit when/if:

1. The main PCB of either unit is malfunctioning.
2. The DIP switches of the system are not working well.

Solutions:

1. Check the wires harness of the PC board and DIP switches for damages. Repair the damaged wires and loose connectors where needed.
2. Seek professional help to inspect the PC board and DIP switches of the system. Replace either of the spare parts if it’s malfunctioning.

Rinnai air conditioner error code 71

Causes:

This error is triggered on the AC unit when/if:

1. The solenoid valve or solenoid valve circuit is malfunctioning.

Solutions:

1. Check the wire harness of the solenoid valve and circuits for issues. Do the repairing work as needed.
2. Seek assistance from a paraprofessional HVAC engineer to inspect the valve. Replace it if broken.
3. Inspect the main PCB of both indoor and outdoor units. Replace either of the PCBs if it is faulty.

Rinnai air conditioner error code 72, 73, 79

Causes:

This error is reported by the unit when/if:

1. The flame-sensing device is not working.
2. The flame-sensing sensor has gone bad.

Solutions:

1. Try the same solutions as suggested for the Rinnai air conditioner “Error Code 31”.

Rinnai air conditioner error code 00, LC0, LC1, LC2

Causes:

This error is displayed on the unit when/if:

1. The system is detecting a scale build-up in some parts of the unit, especially in the heat exchanger.

Solutions:

1. Flush the heat exchanger and remove all that is not necessary for the component. Replace the heat exchanger if it is malfunctioning.
2. Check the tray at the bottom of the unit. Just turn OFF the water flow to the system.
3. Seek professional help to inspect the whole system for any leakages. Repair the leaks immediately before starting the unit again.

Rinnai air conditioner error code SS

Causes:

This error is reported by the unit when/if:

1. The system is warning you that it is time to do the system service. The SS stands for Service Soon.

Solutions:

1. Simply flush the heat exchanger and do other minor services of the system to take this error down.
2. After flushing, press the ON/OFF button 5 times within 5 seconds to remove the error from the system.