How To Fix Rinnai Tankless Water Heater Error Code 63?

Published & Fact Checked by
Published on:
Last Updated on July 22, 2023

» Home » Error Codes » Electronics Products » How To Fix Rinnai Tankless Water Heater Error Code 63?
Rinnai Tankless Water Heater Error Code 63

The Rinnai Tankless Water heater is very popular among customers for its technical capabilities of the device.

These advancements in technology also have one more major use which is pointing out the issues with the device in the form of error codes. Rinnai has many different error codes that are explained with the reasons and solutions on the website to help the customers in case they happen to run into the issue.

In this article, we will discuss the Rinnai error code 63.

This error code shows up when the circulation flow on the heater drops below 1.3 GPM. there can be many reasons for this to happen.

We will discuss the solutions that you can try before you have to contact a technician. Let’s move to the next section to discuss the solutions.


How to solve the Rinnai error code 63?


The tankless water heater needs to maintain a steady circulation flow. If the circulation rate drops below the recommended range, you will see the error code.

Let’s explore the reasons for the issue and how can you exactly get rid of each one in this section.

Fix 1: Check the low rate on the device

As the discussed issue is already mentioned as the circulation rate being low, the first thing that you should take is to check the circulation rate on the device.

For the unversed, here is how you can do it.

  • Find the Temperature controller
  • Find the “UP” button 
  • Press the “UP” button for around 5 seconds 
  • Then press the ON/OFF toggle switch.
  • The circulation rate of the device will be seen now.

Check the displayed rate of circulation and match it to the recommended standards shared by Rinnai.

You need to take action about the circulation rate if it is lower than 1.3 GPM.


Fix 2: Check the inlet pressure of the heater

The inlet and outlet pressure of the tank needs to be managed in order to maintain the circulation flow of the Rinnai water heater.

If you are facing a circulation error then it is possible that the inlet pressure of the tank is off balance.

Check the inlet pressure of the tank and make sure that the value is between 30 psi to 50 psi. If it is not, you need to get the inlet pressure fixed.


Fix 3: Let the air out from the pump and system tank

After you have checked to see if the circulation rate on the water heater is less than 1.3 GPM, the step that you can take to increase this value to an acceptable value is letting air out of the pump and the system tank.

Removing the air from the system tank on the heater will reduce the undue pressure on the device and will allow the circulation to get better.


Fix 4: The inlet water filter should be clean

The inlet water filter is responsible for getting the water inside the heater. If the inlet water filter is not cleaned for a long time, there will be debris accumulation in it.

The debris accumulated will not let the water inside the heater at the speed that it should. Hence, the circulation rate of the water heater will drop below the acceptable level. 

Make sure that you clean the water filter on a regular basis and even if you have forgotten this up until now, you can take care of this when the error code has drawn your attention toward the issue.


Fix 5: Check the flow rate of the inlet pump

As we have already mentioned in the point above, a steady flow of water is important for maintaining the circulation rate on the water heater.

The inlet pump needs to supply water at a steady speed so that the water can flow and complete other processes in the device with ease. 

You can check the flow rate of the inlet pump. If the flow rate is below 6 GPM, you need to get it fixed.


Fix 6: Perform a hard reset on the device

One of the possibilities while witnessing this error code is that there is no underlying issue but the error code is showing up due to a technical glitch.

You can take care of this technical glitch by performing a hard reset on the heater. If the error code disappears after the hard reset, then it is safe to assume that there was no issue with the heater and that it was a false alarm.

You can perform the hard reset by switching off the power to the heater, waiting a while, and then switching the power back on.


Fix 7: Contact a technician for help

If none of the above solutions have made sense to you, or you do not know how to execute these solutions, you will need help from an expert technician.

You can call in a technician that you know or you can directly contact Rinnai support and ask them to help you with the issue. If the issue is small, they will walk you through the troubleshooting process but if the issue is big, they might send in a technician to help you with it.


To conclude


The error code 63 on Rinnai tankless water heater is an issue with the circulation rate on the device.

If the circulation rate falls below 1.3 GPM,  you will see this error code. We have mentioned the solutions that can help you with the issue but we recommend that if you are not an expert in electrical devices, do not mess with the connections of the device on your own. It is always a better idea to ask for help from someone who specializes in electrical repair.

We hope that this was a helpful insight into error code 63 and you were able to get rid of the error code.

Keep following for more technical advice.


Like This Post? Checkout More

Photo of author
Falguni Rana is a technology writer who has expertise in software and hardware troubleshooting. She publishes how-to and troubleshooting guides for different apps, websites, games, and consumer hardware products.