Navien is a top choice among tankless water heaters, known for providing an unlimited hot water supply with minimal maintenance. As a homeowner who has relied on Navien for years, I’ve experienced firsthand their reliability, but I’ve also encountered occasional issues like inconsistent water temperatures.
With a long life expectancy and high energy efficiency, Navien stands out, though it’s essential to understand and troubleshoot potential problems.
Knowing and addressing potential problems ensures a consistent hot water supply when needed, preventing any inconvenience or discomfort. Moreover, fixing minor issues is more cost-effective than dealing with major breakdowns.
Common Navien Tankless Water Heater Problems
To keep your hot water flowing smoothly, here are some common problems in Navien tankless water heaters and how to fix them.
● Error Codes
Navien tankless water heaters simplify troubleshooting with built-in error codes. Through years of troubleshooting these units, I’ve seen that addressing these codes quickly can prevent larger issues. For example, Error Code E003 indicates an ignition failure and can often be resolved by ensuring the gas supply valve is open—a small but crucial fix.
- Error Code E003 – Ignition failure: Ensure the main gas supply valve is open.
- Error Code E004 – False flame detected: Check the electrical cord for proper grounding.
- Error Code E012 – Flame loss: Unplug the unit, clean the intake filter, and restart.
- Error Code E515 – Unusual operation of the PCB: Check the electrical cord’s grounding.
- Error Code E760 – Time to flush your water heater: Refer to the manual or contact a plumber.
For other codes, it’s advisable to consult a service technician.
● Cracked Heat Exchanger
A cracked heat exchanger can lead to the escape of toxic gases and is irreparable. In such cases, upgrading to a newer Navien tankless water heater is the solution.
● Control Board Failure
If your unit repeatedly shuts on and off, it may indicate control board issues. Contact professionals for evaluation and potential replacement.
● Noisy Operation
Unusual sounds from your unit could be due to loose parts, a water line vacuum, a defective pressure valve, or a dirty flow sensor. Professional assistance is recommended to address these issues, especially if the unit is under warranty.
● Recirculating Pump Issues
Ensure the heater is set to recirculation mode as per the user manual. If problems persist, consult a professional to verify the installation.
● Water Isn’t Staying Hot
Several factors can cause fluctuations in hot water delivery, including simultaneous heavy usage, low gas supply, damaged flow sensor, or a pilot light that won’t stay lit. In some cases, these issues may also result in unexpected bursts of cold water. You can consult a professional for diagnosis and repairs.
● Tripping Breaker
Suppose your Navien tankless water heater trips the breaker. In that case, it may be due to a damaged unit or water leakage into the wiring. If no leaks are found, further electrical troubleshooting is needed.
Navien Tankless Water Heater Not Heating
A malfunctioning flow sensor is a common cause of a lack of hot water in a Navien tankless heater. This critical component monitors the water flow rate. From my experience, if the flow sensor becomes faulty or corroded, it fails to signal the controller properly, leading to a loss of hot water.
A quick solution involves inspecting the sensor for debris, but replacement might be necessary if the issue persists.
Sensor corrosion can be a recurring problem for older models, and replacing it with a stainless steel version is recommended. Installing a water inlet filter can also help eliminate water impurities that damage the flow sensor. Consider upgrading to a newer model if problems persist with an aging unit.
Navien Tankless Water Heater Standby Mode
Navien tankless water heaters feature Standby, operational, and error modes. Standby mode, indicated by a green screen, allows the heater to await activation. It may enter standby mode if hot water demand exceeds capacity or the water temperature reaches a safety threshold.
Read also: What is the Downside of a Tankless Water Heater?
A simple reset is usually sufficient to deactivate standby mode. This method should successfully deactivate the standby mode and restore your Navien tankless water heater.
So, how do you reset the Navien tankless water heater to deactivate the standby mode? Here’s the guide:
- Press the Back button on the front panel.
- Disconnect the power cord if using a GFI outlet.
- Flip the breaker in the breaker box to the off position, wait 30 seconds, and then restore power.
Navien tankless water heaters are known for their exceptional performance but may encounter problems like any appliance. To prevent common Navien tankless water heater problems and ensure your unit operates at its best, you can do regular maintenance or ask for professional assistance.
| Maintenance Task | Frequency | Notes |
|---|---|---|
| Descaling the Heat Exchanger | Every 6-12 months | Use a descaling solution for best results |
| Cleaning the Cold Inlet Water Filter | Every 3-4 months | Prevents flow issues and sensor malfunction |
| Checking and Cleaning the Air Intake Filter | Every 3-4 months | Ensures efficient combustion |
