Reset Your Navien Tankless Heater: A Simple Guide

Experiencing issues with your Navien tankless water heater can be a real inconvenience, especially when you’re looking forward to a warm shower. Before you call in a professional, there’s a simple solution you might want to try: resetting your unit. In this guide, you’ll learn how to safely and quickly reset your Navien tankless water heater to get it back to its optimal performance.

Understanding how to reset your water heater is not just about fixing immediate issues; it’s also about maintaining the longevity of your appliance. We’ll walk you through the steps to ensure you’re never left in the cold. Keep reading to find out how to tackle this task like a pro.

Why Should You Reset Your Navien Tankless Water Heater?

Resetting your Navien Tankless water heater is vital for several reasons. At times, electrical glitches might cause the unit to malfunction. These are often temporary and easily corrected with a simple reset, avoiding unnecessary service calls.

Efficiency is key to the operation of your tankless water heater. A reset can clear potential error codes that may cause the system to run less efficiently, ensuring that you always get the maximum performance.

Regular resets can also preemptively address small issues before they evolve into bigger problems. For instance, it prevents scale build-up, which is a common issue in tankless units that could lead to a reduction in water flow.

Moreover, the reset process can extend the lifespan of your water heater. Just like with any technology, keeping your Navien unit in top shape through periodic resets can help maintain its parts, reducing the likelihood of premature failure.

Let’s not overlook safety. Your water heater is equipped with numerous sensors and safety mechanisms. A reset ensures these systems operate correctly, keeping you and your home safe from potential hazards such as overheating or gas leaks.

Lastly, routine maintenance, which includes resetting, is often a stipulation in the warranty terms. To keep your warranty valid, you’ll need to adhere to these maintenance practices, which Navien prescribes for optimal operation.

Remember to follow the step-by-step instructions outlined to reset your system accurately and safely.

Safety Precautions Before Resetting Your Navien Tankless Water Heater

Before attempting to reset your Navien tankless water heater, it’s critical to take certain safety precautions. Adhering to these measures can prevent accidents and ensure your well-being.

  • Turn Off the Power Supply
    Always turn off the power supply before you start the resetting process. This avoids the risk of electric shock and protects the water heater’s components from potential damage due to sudden power surges.
  • Check for Gas Leaks
    Inspect the area for any smell of gas. If you detect a gas leak, do not attempt to reset the water heater. Instead, evacuate the area and contact emergency services or a professional technician to handle the situation.
  • Allow the Unit to Cool Down
    If your water heater was in operation, give it ample time to cool down. Opening the unit or trying to reset it while it’s still hot can lead to burns or other injuries.
  • Use Proper Tools
    If adjustments are necessary for the reset, make sure you use the correct tools. Using improper equipment can cause damage both to the water heater and to yourself.
  • Wear Protective Gear
    Consider wearing gloves and safety glasses to protect your hands and eyes from any possible splashing or debris.
  • Consult the Manual
    Prior to the reset, consult the water heater’s manual. It contains specific instructions and safety warnings relevant to your Navien model.

Remember, your safety is the priority. If resetting your water heater feels overwhelming or if you come across any complications not covered in the manual, it’s best to seek professional assistance.

Step 1: Shut Off the Power Supply

Safety must be your top priority when handling any maintenance on your Navien tankless water heater. The first step in resetting your unit is to shut off the power supply. To do this, locate your water heater’s circuit breaker in your home’s electrical panel. This will be a dedicated breaker labelled accordingly. Flip the breaker to the “Off” position, ensuring that there is no electrical current flowing to the heater.

Turning off the power is crucial to prevent any accidents and ensure a safe environment for the reset process:

  • Eliminates the risk of electrical shock
  • Prevents damage to the unit’s electrical components
  • Ensures your safety and the safety of those around you

After you’ve successfully shut off the power supply, double-check that it’s indeed off. You can test if the appliance has been properly powered down by checking the unit’s control panel or attempting to activate the hot water tap. If the control panel is inactive and the water heater doesn’t respond to the hot water tap, you can be confident that the power supply is disconnected. It is only after this confirmation that you should proceed to the next step in the reset process—inspecting for gas leaks. Remember, if you detect any smell of gas, do not attempt any further steps and immediately contact a professional for assistance.

Step 2: Locate the Reset Button

Once you’ve confirmed that your Navien tankless water heater is powered down and free from gas leaks, you’ll need to locate the reset button. It’s usually situated on the front panel of the unit for quick access—a testament to the user-friendly design of Navien products.

Reset buttons are typically red or yellow, this colour coding is a universal sign indicating action is required. Your Navien’s reset button might be clearly labelled or it could be situated near the control panel. If you’re struggling to find it, don’t hesitate to refer to your owner’s manual. The manual will provide you with a detailed diagram of the water heater’s components, helping you to identify the location of the reset button.

Bear in mind, the design of Navien tankless water heaters can vary across different models. So, it’s important your manual corresponds with your specific model number. If you’ve misplaced your manual, don’t worry; Navien’s customer support often offers downloadable versions online, or you can request a physical copy.

Once found, the reset process is straightforward. Gently press the button and wait for a response from the system. Most units will have a light indicator that flashes or changes color to signify a successful reset. Ensure you don’t press too hard or repeatedly as this may harm the button mechanism or the electronic components behind it.

Step 3: Press and Hold the Reset Button

After locating the reset button, it’s time to actually reset your Navien tankless water heater. Press and hold the reset button for a precise duration: typically, 5 seconds is recommended. This is a critical step – pressing for too little time may not trigger the system’s reset protocol, while pressing for too long can sometimes cause the system to enter a diagnostic mode.

While holding down the reset button, watch for any visual cues such as flashing lights or hear a click sound that indicates the system has acknowledged the reset command. Navien water heaters are designed with user-friendly interfaces, making it fairly obvious when the system initiates a reset.

Release the button after the visual or audible confirmation. At this point, the unit should begin the resetting process. You’ll notice the water heater powering down momentarily before restarting. This is normal behaviour reflecting the system’s internal processes resetting. Here’s what you should keep an eye out for:

  • Shutdown of the heater’s display or control panel
  • Audible click or beeping sounds indicating a restart
  • The system may display error codes if there are any issues

Tip: If your Navien unit doesn’t restart automatically after the reset, turn off the power supply to the unit for about 30 seconds, then turn it back on. This can help to ensure that the reset is fully engaged and the system resumes its normal operation.

Remember, safety is paramount. If at any point during the reset process you feel unsure or encounter issues, don’t hesitate to contact Navien’s customer support for guidance. Professional assistance can help resolve any complexities without risking damage to your unit or your safety.

Step 4: Wait for the Unit to Reset

After you’ve pressed the reset button on your Navien tankless water heater, it’s crucial you give the unit time to reset. This pause allows the system to clear any error codes and restart its heating functions.

Allow the system to rest for a full minute. During this interval, your Navien is undergoing internal checks to ensure it’s ready for operation. Watch the display panel closely; it should indicate the reset process with specific codes or lights that signal a reboot. Typically, the water heater will display a standard operation screen once it’s ready.

Resist the urge to press any buttons during this waiting period. Doing so can interrupt the reset process and require you to start over. Patience here is key.

If your water heater has an error memory function, the system might retain previous error codes. This feature helps users and technicians diagnose recurring issues. For newer models, check the manual to see if the reset clears the memory or if further steps are required to erase error history.

Remember, if the unit has not restarted after the minute has elapsed, consult your Navien user manual for model-specific instructions or troubleshooting tips.

Step 5: Turn the Power Supply Back On

After ensuring that your Navien tankless water heater has had adequate time to reset, it’s time to reignite the system. Re-establishing the power supply is a straightforward process, but timing and attention to detail are crucial for a successful reboot.

First, locate the power switch or plug for your water heater—this will typically be found in a utility room, basement, or wherever your unit is installed. Once you’ve found the switch or outlet, it’s crucial to turn the power back on in a controlled manner. Flip the switch or insert the plug firmly to restore power to your water heater.

As the system powers up, keep your eye on the display panel. It should come to life, indicating that the Navien heater is receiving power. You’ll want to watch for any error codes that may appear; these codes could provide important information about the status of your heater.

In some cases, your water heater may take a few moments to begin its startup sequence. Listen for the sound of the unit initiating and watch for the confirmation that the ignition process has completed successfully. It’s also advisable to check for signs of normal operation, such as audible cues or the feel of warm water from a tap.

Monitor Performance and Functionality

Once the unit is back on, you’re tasked with monitoring to ensure everything is running smoothly. Keep an ear out for any unusual noises and keep an eye on the display for any alerts. The first few minutes after restarting your tankless water heater are crucial in detecting any immediate issues.

If all goes well, your Navien tankless water heater should now be operational and ready to provide a consistent supply of hot water. Remember, routine maintenance and immediate attention to any error codes can extend the life of your heater and ensure peak performance.

How to Troubleshoot Common Issues After Resetting Your Navien Tankless Water Heater

Once you’ve successfully reset your Navien tankless water heater, you may encounter some common issues that require troubleshooting. Understanding these problems and knowing how to address them will help maintain the longevity and efficiency of your unit.

Check for Error Codes

Your Navien water heater’s display panel is your go-to diagnostic tool. After a reset, the panel may show new error codes, which you’ll need to decipher:

  • Error Code E003: Ignition Failure
    This could mean gas supply issues or that the ignition pack isn’t working.
  • Error Code E010: Abnormal Exhaust Temperature
    Check the vent pipe for obstructions or debris build-up.

Inspect the Water Flow

Low water flow can prevent your water heater from operating correctly. Here’s what to do:

  • Clean the inlet water filter.
  • Ensure that the water supply valves are fully open.

Listen to the Unit

After a reset, listen carefully to your water heater. Any unfamiliar noises might indicate an issue:

  • Rumbling or knocking could mean mineral build-up.
  • Whistling may suggest a gas supply problem.

Monitor Water Temperature

Fluctuations in water temperature can be symptomatic of larger issues:

  • Inconsistent heating can signal a faulty flow sensor.
  • Sudden temperature changes may point to a malfunctioning thermostat.

Check Gas Supply

In some cases, the issue might stem from your gas supply line:

  • Verify that your gas valve is fully open.
  • Check other gas appliances to confirm there’s not a wider problem.

Consult the User Manual

Your Navien tankless water heater comes equipped with a detailed user manual containing model-specific troubleshooting advice.

  • Refer to the manual for codes not covered here.
  • Follow the manufacturer’s instructions for complex issues.

By paying close attention to your Navien tankless water heater’s behavior and using the provided error codes as a guide, you’ll be well-equipped to identify and solve many common problems. Remember to maintain your unit regularly and perform routine checks, as preventive care is often the best approach to ensuring your water heater’s optimal performance.

Regular Maintenance Is Key

To prevent future issues and maintain efficiency, keep up with regular maintenance. This includes:

  • Descaling the heat exchanger annually.
  • Replacing the air filter as recommended.


Resetting your Navien tankless water heater can seem daunting, but with the right guidance, you’ve seen it’s quite straightforward. Remember to allow your unit the necessary time to reset properly and address any error codes that may appear. Should you encounter issues like low water flow or temperature fluctuations, the troubleshooting tips you’ve learned will come in handy. Don’t forget that regular maintenance is key to your system’s longevity and efficiency. If in doubt, your user manual is your go-to resource for model-specific advice. With these tips in mind, you’re well-equipped to keep your water heater running smoothly.