Rinnai Tankless Water Heater Error Codes- Troubleshooting Rinnai Errors

Rinnai tankless water heater error codes are a common problem that most people face nowadays. Although tankless water heaters are the great appliances that everyone uses nowadays due to several advantages which they are providing but at the same time, just like many other appliances, they can face damages due to external or internal reasons.

Tankless heaters save energy, time, and money by offering instant hot water, yet at the same time, they may cause the lousy quality of hot water. Most people are worried about Rinnai tankless water heater not being hot enough. So, before going into solving this problem, you must know the reason behind it to solve an error by keeping an eye on the issue.

Down in this section is detail on Rinnai tankless water heater not getting hot enough reason and the relevant solutions to troubleshoot. You may also get how to check the Rinnai error codes and how to solve them.

Rinnai Common Error Codes and Troubleshooting These Codes 2023

Here are some running error codes at your tankless water heater’s screen, which are why Rinnai tankless water heater is not heating. Among these Rinnai r75ls problems is a top problem related to a standard error code.

Here are some issues codes/troubleshooting and the solution of the specific situation.

ERROR CODE 02

When there is an error code 02, there is no burner operation and protection mode; you need to call a plumber who will solve this issue. Don’t try to solve anything or try anything yourself until a plumber advises you.

ERROR CODE 03

This is due to power interruption during batch fill. It’s usually so don’t worry much about it

If there is a power interruption due to any reason and even your power resource is restored after some time, your heater cannot provide enough hot water. It is another Rinnai tankless water heater problem, and you can solve it by using the following ways:

Look at all the hot water fixtures at your home, and if they are ON, then you need to shut them off

Now try to turning On and Off the temperature controller button, in this way the water flow may starts

In the end, if you are still facing any issues, you need to call a plumber at this time

ERROR CODE 05

This error occurs due to bypass valves in the heater.

In this case, you should follow these steps:

• Turn off the power resource of a tankless heater
• Now turn on the power of the tankless water heater
• The error typically ends in most cases. And if this is still persistent, you need to call several professional

ERROR CODE 10

This is due to blocking the air supply pathway or due to blocking the exhaust blockage

In this case, follow these steps and guide:

Check the reason for blocking air pathway and clean that pathway warmly

In case if you find the issue resolved in this way, that’s good, and if you find the problem is still persistent, you need to call the plumber.

ERROR CODE 11

This error is due to No Ignition, and here are the steps to remove this error!

First of all, call a professional or plumber because it’s not a light error that you can solve by yourself. However, implement these practices when you are unable to find a plumber!

Check the gas valve properly and see if it’s On or Off. In case if it’s off, you need to turn it on.

Now check the ignitor to see if it’s working correctly and if it’s not working, then you need to call a plumber.

ERROR CODE 12

This error code is not as simple as other error codes are where you can solve yourself or call a plumber. Here, the issue creates two main reasons, but first, you need to determine the error code. Here are some ways which can help you to recognize the actual problem.

When the heater is going in the ignition cycle, you need to check the window and the flame if it’s visible or not, and if you see a flame during this cycle, it means it’s an error code 12 issue there. This is flame failure gas code error 12

And if the flame is not available there, it means there is immediate also called electrical error code 12

Note: so, here, the most critical challenge is to determine if the error code is due to gas or due to electricity after knowing that t’s easy to implement the relevant solution.

Flame Failure Gas Code Error and Solution

This problem is not so simple that you can handle it yourself. Call a plumber of an experienced man to solve this error to get rid of the Rinnai water heater not heating.

Immediate Electrical Error Code 12 Solution

Here are the considerations to get rid of this error:

This code means that there is an issue in the circuit, the wiring issue, bypass valve issue, or if there is sudden water flow control n the water pathway

In this case, unplug the circuit and see if t’s work again after plugging it into the same circuit. If the issue gets resolved, then it’s good. In either case, you need to call a plumber or professional.

ERROR CODE 14

Thermal code 14 has different situations, which are given below, and you should implement the relevant solution.

Thermal fuse error code 14 means that your tankless water heater is overheating, mainly due to the thermal fuses or the bi-metal safety switch issues.

In this case, you should remove the overall cover. Now check and see the exchanged color on the copper boxes. If it happens, now check the internal parts and disconnect them all or detach the fused circuits

The solution is that there should be no airflow in the whole unit and system. Also, see that there is enough cold air coming towards the airflow system, which is needed for the excellent working of the heater.

ERROR CODE 16

It’s an indication of an over-temperature warning, which means that the unit is suddenly too heat.

To solve this error, you must keep in mind that there is enough airflow on the system. Also, see the amount of air inhaling and exhaling by the Rinnai heater should be enough. See the heater exchanger and clean the heat exchanger fins. In the end, you may also need to replace the heater exchanger system on the heater.

ERROR CODE 19

It means that there is an electrical grounding fault. And it means that there is a short electrical issue in your components.

In this case, confirm that all the shocks and circuits are working fine. In the end, call a professional who can solve this troubleshoot quickly.

ERROR CODE 25

The error means that the condensate trap is full from all the ways.

In this case, check for the condensate line and the trap for the blockage. It should work fine, and you can see this by checking enough gaps between the unit and the drain line. Also, check for all the connections, and there should be no loose, broken, or incomplete connections. Solve immediately if there is any. You can check this code by the sensor, and if the error still shows after implementing all the ways, you need to change the sensor again.

ERROR CODE 30

It means that there are flammable vapors.

We recommend not going towards the area where the water heater is already installed as, firstly, it’s needed to identify where the water heater vapors are persistent.

To eliminate this error, check that there are no external or internal wiring issues in the overall system, check and confirm that there is no broken error. Make sure that there are no flammable vapors. After that, again, turn on the gas or electric power and check the issue. If the sensor still dominates the problem, you need to change the sensor.

ERROR CODE 31

If this error code shows on the sensor, there is an abnormality in the burner thermocouple, which should be resolved in the following ways.

Firstly, you have to ensure that the dip switches and high fire manifold are attached correctly. Set the thermocouple and all other circuits related to the burner rightly. If everything is fine, then you need to replace the thermocouple. And if the problem is still present, you need to call a professional for this purpose.

ERROR CODE 32

This error means that your outgoing water temperature sensor has abnormalities, i.e., in the thermistor, and you need to correct it.

To solve this issue, make sure that there is no issue with the thermistor and no broken connections. Check all the resistances and readings if there are working fine. The end performance replaces the thermistor because the error is due to this.

ERROR CODE 33

It means that your Heat Exchanger Outgoing Thermistor is not working fine, and you need to make changes here.

Again check and make sure that the thermistor has no loose or broken connections from any side. Also, check the resistances and readings if there are working fine or not. In the end, replace the thermistor, which is the only solution. However, if you are unsure about your thermistor, you should call a professional to solve this error code.

ERROR CODE 34

This error is due to Combustion Air Temperature Thermistor failure, and it needs complete attention to solve. This error mainly occurs in indoor tankless water heaters.

Firstly, to fix, check and make sure that there is no loos or broken connection in the thermistor. After that replacing your thermistor would be better instead of wasting time.

ERROR CODE 35

This error means Tank temperature sensor abnormality. And here is the way to fix it!

See and make sure that there is no loose tank connection with the sensor. Also, check all the resistances and ensure there is no error in reading the whole sensor. If the error is still persistent, you need to call a plumber.

ERROR CODE 38

This error is the most complicated, which means CO sensor abnormality (RH-180 only).

To fix it, make sure that all the components of 4″ B-Vent venting materials are installed successfully, and there is no issue there. Now confirm and check if the dip switches are installed and work correctly. Also, make sure that there is enough inline gas supply there. Now replace the sensor and the onboard checker.

ERROR CODE 41

This error means that there is an abnormality in Freeze Protection Sensor. And this error mainly occurs in the outdoor tankless water heater models. And it happens when the outdoor air thermistor is disconnected from the heater.

Reattach the thermistor with the heater to solve this, and the error will be clear. Here are some more recommendations which are necessary to check.

Check for all the wires and the connections and make sure that these are not attached loosely, even if some of the models show clear reading when the error code is eliminated. However, we recommend checking all the connections to avoid any wrongful conduct or the outcoming issue you may face.

ERROR CODE 52

Error 52 indicates Modulating solenoid valve signal abnormality (POV) is another significant error you need to see by an in-depth analysis.

To solve this error, confirm the connectivity of the POV valve with all other switches, and there should be no damage or looseness anywhere. Check the resistance and readings to see if they work fine after confirmation that connections are not damaged or loose. If the error still exists, you should call a professional to eliminate this error ideally.

ERROR COSE 57

This error means the Burner is overheated with Burner overheat bi-metal switch fault.

To solve and get rid of this error, again check the POV valve if it’s working fine and has all the connections as they should be. Please turn off the Burner once and turn it ON again. Now check the sensor, and the error will be eliminated. Directly it would help if you changed the sensor or the PC board. However, if it still exists, you need to check the professional.

ERROR CODE 58

This error means that there is a fault in the secondary heat exchanger sensor, and it mostly happens when two bi metals open at the rear of the secondary heat exchanger.

Firstly, to solve this error, confirm that there are no loose or damaged connections at the sensor wiring areas. Also, check the scale build-up on the sensor which is needed and see if the water flushing is correct. In case of water flush strangely, then it means that your water is complex and needs to treat.

ERROR CODE 61

This error means that there is a fault in the combustion fan motor.

To solve this error, you should make sure that there are no damages or loose connections. Correct these connections if these are not fine. Remove the motor fan and use a tool to make movements in the motor. Now, if the motor moves freely all around, attach it again to the connection and see if the error is eliminated. On the other hand, if the error still exists, you need to replace the motor with a new engine. We recommend calling a professional for this purpose.

ERROR CODE 63

This error occurred when the Circulation flow rate dropped below 1.3 GPM.

To solve this error, follow these steps:

In the Rinnai tankless water heater, there is a temperature controller. Check the temperature and turn it off; now again, turn it on. At that time, the displayed flow rate is 0.7 GPM, 2.5 GPM, or between these values for minimum and maximum value.

• In case if you find the flow rate below 1.3 GPM, remove air to form the whole system using the pump and remove air from the pump.
• Also, remove and clean the inlet filter correctly
• Now check if the water pressure is 6GPM or higher

Note: if it’s 6GP or higher, it means that your heater is now working well. You need to call a professional to solve this error in another case.

ERROR CODE 65

This error is primarily due to Water flow control which is easy to solve and may need to call a professional if it exists after your trial.

To solve it check and make sure that all the connections are working fine. Specifically, the contacts on the water flow server should not be broken. In this case, you should turn off the power unit after confirming the connections and see if the error is eliminated. On the other hand, if the error still exists, there is a critical issue and call a professional now.

ERROR CODE 70

This error is basically due to a PC board fault, and here is the way to solve this error.

To solve it, make sure that there is no breakage or loose connection of the PC Board with all other heater links. The endpoint is to call a professional and replace the PC board if the error still shows after the correction.

ERROR CODE 71

This error is due to Solenoid Valve Fault, and it means that your solenoid valve has been appropriately failed.

There are four solenoid valves, including VSV0, SV1, SV2, and SV3. The error may arise due to damage to any of these valves. In this case, replace the gas valves or dry them because the fallacy occurs because of the moisture in the valves. If the error persists, calling a professional is the end solution.

ERROR CODE 72

This error is due to a Flame sensing device fault.

To solve this error, you should call a plumber. However, here are some solutions or suggestions which you can perform yourself if professional is too far or not available at that time.

First of all, turn off the gas and electricity supply to the Rinnai tankless water heater and scrutinize the PC board. Make sure that there is no broken connection in the board. Also, check the flame rod and look for the carbon build-up and clean it carefully by using a smooth cloth or anything else.

Again check the flame rod and see that no debris is available. In case if you find debris there, clean them out. Again turn On the gas or electricity supply and check the heater at 1-microampere voltage. Most of the time, the error get’s resolved and if the error is still persistent, then call a professional.

ERROR CODE 51

This error means that there is an Inlet Water Temperature Sensor issue.

To solve this error, make sure that all the inlets and the connections are attached correctly. There should be no broken or loose points that are the leading cause. Also, make sure that scale build-up is working fine. Some models show the same error even if you correct and implement the relevant solutions. In this case, must call a professional who can solve and eliminate this error.

ERROR CODE 73

Primarily this error is due to Burner Thermocouple Fault.

To solve this error, check the burner couple fault and see that there should be no broken or damaged connection. If the error still shows, you need to replace the burner.

ERROR CODE 79

This error is due to a water leakage problem, which means that Water Leakage is Detected in your system.

To resolve this error, check and look for the following solutions:

• First, check for the connections and see if the water and heater wires are not damaged. In case if these are damaged, you need to reattach them or replace them.
• Also, check the heat exchange and all internal piping. Make sure that pipes are not leaking and they are working fine.
• Also, check the bottom pan of the pooling and make sure that there is no distraction or leakage. If there is any damage or leakage, then resolve it directly.
• Also, dry out all the sensors and connections once you have connected them all.
• If the problem still exists, then you need to call a plumber or professional.

ERROR CODE EF

It means that Flammable vapors are detected in your system.

The critical warning we want to mention is to leave the area for a time until there is proper safety and precautions.

Check and inspect the flammable sensors and make sure that there is no damage. In case if you are sure that there is no damage, you need to turn off the gas supply and again turn it on. The error will resolve in this way. However, if it is still present, you need to call a professional.

ERROR CODE FF

This error code means that the maintenance has been performed recently. It indicates Rinnai tankless water heater no hot water no error code.

This is not a big issue, and you do need to worry about it. The error is quickly eliminated once you turn off and turn on the overall system.

ERROR CODE LCO

This error means that there is a limescale build-up in your system.

The recommended procedure for clearing the code is as follows: Flush out all of your unit’s vital fluids and press the on/off button five times. This should reset it, so you don’t have to worry about another LC Lock Code coming up within 70 hours after doing this temporary fix!

NO ERROR CODE

If there is no error code and your heater does not work fine, it means that nothing is happening to the system and your water flow works fine. To solve this error, you need to check the following:

If you just installed a tankless water heater, ensure that the hot and cold lines are correctly attached. If they’re reversed, it won’t work!

Check that the minimum flow rate is met. If you are not meeting this requirement, it may result in an inefficient firing process which could lead to issues with the performance and efficiency of your system.

Check that the water flow control turbines are spinning freely. They should be able to turn without obstruction by dirt or other objects, and if not, then clear away any obstacles from them immediately because this will cause an issue with your plumbing system later on!

Do you ever find yourself in the middle of a steamy shower only to be met with cold, unheated water? This is not ideal. If this has happened to you, there are three possible reasons for being wrong. Your Rinnai tankless water heater might need repairs or replacement; it may require an adjustment or Rinnai r75ls troubleshooting may be necessary.

There may be many other reasons, basically including the error code. Check the troubleshoot and then solve according to the appropriate method.

Note: Here are some of the best rated Rinnai tankless water heaters which have very few chances of these error codes because of their excellence!

• Rinnai RL75iN Natural Gas Tankless Hot Water Heater
• Rinnai V53DeP Propane Tankless Hot Water Heater

Rinnai Tankless Water Heater Error Codes – Final Verdicts

Hence, Rinnai Tankless Water Heater Error Code is due to various reasons. Above are complete details about these errors and how you can resolve these errors. Follow the above guide and eliminate the error within seconds. For more information and updates, keep reading our latest blogs.

Do you ever find yourself in the middle of a steamy shower only to be met with cold, unheated water? This is not ideal. If this has happened to you, there are three possible reasons for being wrong. Your Rinnai tankless water heater might need repairs or replacement; it may require an adjustment or Rinnai r75ls troubleshooting may be necessary.

There may be many other reasons, basically including the error code. Check the troubleshoot and then solve according to the appropriate method.

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