Noritz Tankless Water Heater Troubleshooting

Noritz Tankless Water Heater Troubleshooting

  • Troubleshooting any tankless water heater is not a walk in the park. It requires a lot of patience and expertise, which we’ll help you understand in this article. The article explores some important and helpful Noritz tankless water heater troubleshooting tips.

Noritz is one of the industry’s biggest names as far as tankless water heaters are concerned. The Japanese brand has survived many decades of competition in the market to become one of the most successful tankless water heater brands. Noritz tankless water heaters are famous for their energy efficiency and fast heating speeds.

Despite being known for their efficiency and durability, you must learn something about troubleshooting Noritz tankless water heaters if you ever encounter any issues. You must understand how to troubleshoot your Noritz tankless water heater, especially if you have a large family and you use the water heater often.

In this article, we’ll explore several Noritz tankless water heater troubleshooting tips to help you understand how to troubleshoot your tankless water heater whenever an issue arises. We’ll also look at the pros and cons of Noritz tankless water heaters, so if you’re considering buying one, you can make an informed decision and not make a mistake.

Pros and Cons of Noritz Tankless Water Heaters

Tankless water heaters, such as those manufactured by Noritz, have gained popularity recently due to their energy efficiency and on-demand hot water capabilities. However, like any appliance, they come with their own set of advantages and disadvantages. Below is a list of what makes Noritz tankless water heaters stand out and where they might fall short.


Compact design

Noritz tankless water heaters are significantly smaller than traditional water tanks. They can be wall-mounted and occupy much less space, making them an excellent choice for homes with limited square footage.

Check out our list of the best electric water heaters for RVS here.

Modern features

Noritz tankless water heaters are often packed with advanced features, including digital temperature controls, self-diagnostic systems, and remote monitoring capabilities. A tech-savvy user praised how they could easily adjust the water temperature through their smartphone app and receive notifications if any issues arose.

Energy efficiency

As one of the most reliable tankless water heater brands in the world, one of the significant advantages of Noritz tankless water heaters is their energy efficiency. Traditional tank-based water heaters continuously heat and reheat the stored water, leading to standby heat loss.

Noritz tankless water heaters, on the other hand, heat water only when needed, eliminating the energy wasted in maintaining a constant temperature. This can result in considerable energy savings over time.

Longer lifespan

While traditional water heaters may last around 10-15 years with proper maintenance, Noritz tankless water heaters are known for their durability and can last up to 20 years or more. Many have lauded Noritz’s effort to make its tankless water heaters last for that long despite their initial purchasing cost, making them a worthwhile long-term investment.


Higher upfront cost

One of the main drawbacks of Noritz tankless water heaters is their initial cost, which can be higher than traditional tank-based water heaters. The purchase and installation expenses can be a significant consideration for budget-conscious homeowners.

Noritz Tankless Water Heater Troubleshooting

Troubleshooting a Noritz tankless water heater should not pose a problem, as opposed to what many may think. Once you’re exposed to the right information, you’ll find the process easier and less time-consuming. Let’s explore some of the problems you may encounter with a Noritz tankless water heater, their possible causes, and how you can potentially solve them.

No hot water

Encountering a lack of hot water can be frustrating, especially when expecting a warm, soothing shower or needing hot water for household chores. Several factors might be at play if your Noritz tankless water heater isn’t producing hot water.

Possible causes and solutions

Power supply issues

The first thing to check is the power supply to your Noritz tankless water heater. Ensure the unit receives electrical power and the circuit breaker or fuse hasn’t tripped. In case of a power outage or a tripped breaker, reset it and see if the water heater starts functioning.

Gas supply problems

If your Noritz water heater is a gas-powered model, verify that the supply is uninterrupted. Check the gas shut-off valve to ensure it is open and allows gas flow to the unit. If the gas supply is cut off, turn the valve on, and relight the pilot if necessary.

Ignition failure

One of the best Noritz tankless water heater troubleshooting tips is to check the unit’s ignition system for any fault. In gas tankless water heaters, an ignition failure can prevent the unit from heating the water. The ignition system may be faulty or obstructed, preventing the burner from lighting properly.

Water flow issues

Tankless water heaters require a certain minimum flow rate to activate and produce hot water. If the water flow is too low, the unit may not kick in, resulting in cold water. Before considering a Noritz tankless water heater repair, check for clogged or restricted water filters, faucets, or showerheads that might impede the flow.

Overheating protection

Noritz tankless water heaters have built-in safety mechanisms to prevent overheating. If the unit detects abnormally high temperatures, it may shut down to protect itself. This can occur due to insufficient ventilation or restricted airflow around the unit. You can hit the Noritz water heater reset button if the unit doesn’t shut down. Click here to see how to reset a Noritz tankless water heater.

Fluctuating water temperature

Experiencing inconsistent water temperatures from your Noritz tankless water heater can be an annoyance that disrupts your shower or other hot water activities. If you face fluctuating water temperatures, there are several potential reasons behind this issue. Let’s explore the likely causes and confidently suggest the appropriate solutions to help you achieve a stable and comfortable water temperature.

Possible causes and solutions

Water flow rate variations

Fluctuating water pressure can change the flow rate, triggering the tankless water heater to adjust accordingly. If the flow rate drops too low or increases suddenly, the water heater might struggle to maintain a consistent temperature.

Ensure that the water pressure in your home is consistent. Check for leaks, clogs, or pressure irregularities in the plumbing system. Consider installing a pressure regulator to maintain a steady flow rate if needed.

Incoming water temperature

The temperature of the incoming water supply can affect the output of your tankless water heater. In colder climates or during winter, the heater might have to work harder to raise the water temperature, potentially leading to fluctuations. Preheating the incoming water can reduce the workload on the tankless water heater in colder climates. Consider insulating the pipes or installing a preheating system to provide warmer water to the heater.

Temperature sensor issues

Tankless water heaters rely on temperature sensors to regulate the water output. If these sensors become dirty, damaged, or misaligned, they may provide inaccurate readings, causing the water heater to respond inadequately. Ensure you regularly inspect and clean the temperature sensors to ensure accurate readings. Contact a technician if the sensors are damaged or faulty to replace them.

Error codes on the display

Encountering error codes on the display of your Noritz tankless water heater can be concerning. These error codes are designed to provide valuable diagnostic information and help identify potential issues with the unit. Understanding these error codes and addressing them can save you time and money.

Possible causes and solutions

Ignition failure (error code 11)

Ignition failure can occur due to gas supply issues, clogged burners, or problems with the ignition system. A failure to ignite prevents the water heater from producing hot water. To solve this issue, ensure the gas supply to the water heater is not interrupted. Confirm that the gas shut-off valve is fully open and there are no issues with the gas line. If the pilot light has gone out, follow the manufacturer’s instructions to relight it.

Flame failure (error code 12)

This code indicates that the burner flame has extinguished during operation. Restricted gas flow, inadequate ventilation, or a faulty flame sensor can cause it. If you encounter ignition or flame failure codes, examine the burners for blockages or dirt. Clean them if necessary. Check the ignition system for proper functioning, and consider professional servicing if required.

Overheating (error code 14)

The water heater’s safety features might detect abnormally high temperatures, leading to an automatic shutdown to prevent damage. Factors like restricted airflow or failed temperature sensors can cause overheating. Ensure that the water heater has sufficient ventilation and is installed in a well-ventilated area for error codes related to airflow. Clear any vent pipe obstructions and follow the installation guidelines meticulously.

Frequently Asked Questions

How do I contact Noritz customer service?

Noritz is always available to listen to customer complaints and concerns. You can check out their contact page on their website for more information.

What should I do if I see an error code on my Noritz water heater’s display?

Error codes indicate potential issues with the water heater. The first step is to consult the user manual to identify the specific error code and its meaning. Common error codes include ignition failure, flame failure, overheating, airflow issues, or water flow problems. Following the troubleshooting tips associated with each code can help address the problem.

How often should I descale my water heater to prevent mineral buildup?

The frequency of descaling depends on your water quality and hardness. In areas with hard water, it’s recommended to descale the tankless water heater every six months to a year. Regular descaling helps maintain the unit’s efficiency and prolong its lifespan. Follow the manufacturer’s guidelines for the descaling process.

Can I install a Noritz tankless water heater in a small closet?

Yes, Noritz tankless water heaters have a compact and space-saving design, which makes them suitable for installation in small spaces or closets. However, it’s crucial to ensure proper ventilation and sufficient airflow around the unit to prevent overheating and ensure efficient operation.

Why is my Noritz tankless water heater not producing hot water?

Possible causes for this issue include power supply problems, gas supply issues (for gas models), ignition failure, or water flow problems. Checking the power source, gas supply and ensuring proper water flow are essential troubleshooting steps.

Final Thoughts

Noritz tankless water heaters offer several compelling advantages, including energy efficiency, endless hot water supply, and a compact design. However, users should know about potential issues like error codes and fluctuating water temperatures. By understanding the troubleshooting tips and seeking professional assistance, users can fully enjoy the benefits of their Noritz tankless water heater while ensuring its reliable performance for years to come. With proper maintenance and attention, these innovative water heaters continue to provide a convenient and eco-friendly solution for households seeking efficient hot water solutions.