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Navien Error Code 003: What It Means and How to Fix It

Written ByAndrew Miles

If you own a Navien tankless water heater, you may encounter an error code 003. This error code indicates a problem with the ignition, and it can be frustrating if you cannot get hot water when needed. However, there are ways to fix this error code, and in this article, we’ll walk you through what it means and how to resolve it.

What is Navien Error Code 003?

Navien Error Code 003 means that there’s an issue with the ignition. Specifically, the heater isn’t able to ignite the gas properly, which can result in a lack of hot water. This error code can occur for various reasons, including a lack of gas supply, a dirty or faulty igniter, or a malfunctioning gas valve.

Causes of Navien Error Code 003:

The Navien Error Code 003 can be caused by several factors, including:

  1. Ignition Failure: This occurs when the system fails to ignite the burner. A clogged or dirty burner, insufficient gas supply, or a faulty ignition electrode can cause it.
  2. Flame Sensor Issue: The flame sensor is responsible for detecting the flame in the burner. If it is dirty or damaged, it may not detect the flame, leading to the Navien Error Code 003.
  3. Exhaust Blockage: If the exhaust vent is blocked, it can cause the system to shut down to prevent the buildup of toxic gases.
  4. Gas Supply Issues: A lack of gas supply or low gas pressure can cause the system to shut down and display the Navien Error Code 003.
Navien Tankless Water Heater Error Code 003 Fixed!

How to Fix & Reset Navien Error Code 003

Here are some quick fixes you can use on your Navien water heater to reset code 003.

1. Check the Gas Supply

Firstly, error code 003 on a Navien water heater typically indicates an issue with the gas supply. The most common cause is a lack of gas supply. To check this, ensure your gas valve is open and your gas supply hasn’t been interrupted. You can also try resetting your gas valve by turning it off and back on.

2. Clean or Replace the Igniter

Secondly, a dirty or faulty igniter can also cause error code 003. If this is the case, you may need to clean or replace the igniter. To do this, turn off the power to your heater and remove the front cover. Locate the igniter and use a soft brush or cloth to clean it. If the igniter is damaged, you may need to replace it.

3. Check the Gas Valve

Thirdly, a malfunctioning gas valve can also cause error code 003. To check this, turn off the power to your heater and remove the front cover. Locate the gas valve and check to see if it’s open. You may need to open or replace the valve if it’s closed.

4. Call a Professional

If you’ve tried these steps and you’re still experiencing error code 003, it’s best to call a professional for assistance. A qualified technician can diagnose the issue and provide a solution that will get your Navien water heater up and running in no time.

Here is a chart outlining the common causes of the Navien Error Code 003 and their corresponding solutions:

IssueSolution
Ignition FailureClean or replace the burner; check the ignition electrode and gas supply.
Flame Sensor IssueClean or replace the flame sensor.
Exhaust BlockageCheck and clear the exhaust vent.
Gas Supply IssuesCheck the gas supply and gas pressure.
Ignition Electrode Damage/WearReplace the ignition electrode.
Severely Clogged or Damaged BurnerClean or replace the burner.
Inadequate Gas PressureContact your gas provider.

Conclusion

Navien Error Code 003 can be a frustrating issue, but it’s not something that you need to panic about. By following these steps, you can diagnose and fix the issue and ensure that you have hot water when you need it. However, if you’re uncomfortable performing these steps alone, don’t hesitate to call a professional for help.

Other Navien Error codes: E001 |

FAQ’s

What causes Navien Error Code 003?

Navien Error Code 003 can be caused by a variety of issues, including a lack of gas supply, a dirty or faulty igniter, or a malfunctioning gas valve.

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