How To Fix Navien Error Code e003 – Best Ways In 2023

Navien Error Code e003: Navien is a well-known and respected brand in the world of portable water heaters. It is known for being very efficient and having a cutting-edge design. But, like any complicated machine, these tools can sometimes have problems that need to be fixed and that require troubleshooting. The navien error code 003 is a common error code that can be caused by several different things.

Some of the most common reasons for this problem are a blocked venturi, a dirty or broken heat exchanger, or a broken pressure switch.  This article aims to provide a comprehensive analysis of navien error code e003 and how to fix it, including its causes and the steps you should take to fix it as quickly as possible.

What is navien error code e003?

On the navien tankless water heater, error code e003 means that there was a problem during the starting process. The unit had trouble getting the stove to start burning, so it didn’t heat the water well enough. The problem is found by the system, and the error code is shown right away to let people know about it. This problem code could show up for several different reasons. Before taking any steps to fix the problem, it is important to go through a structured process of troubleshooting.

Read More: How to Fix SC Error Code On The Samsung Washer

What are the Potential Causes of error code e003?

Insufficient Gas Supply: One of the main causes of navien error code e003 is that the water heater is not getting enough gas. This could be because the gas valve is closed, there isn’t enough gas flow in the supply line, or the gas meter is broken.

Blocked Gas Line: If the gas line is blocked or clogged, gas can’t get to the burner properly, and the burner won’t light. Small bugs or other small things that get into the gas line could cause it to get clogged.

Check the air filter: If the air filter is dirty, the engine might not get enough air to run properly, which could cause the navien error code 003 to appear.

Check the fuel filter: If the fuel filter is dirty, the engine might not get the fuel it needs to run properly, which could cause the navien error code 003.

Check the spark plugs: If the spark plugs aren’t working right, the engine might not get the spark it needs to run well, and the navien error code 003 might appear.

Venting Problems: If the vents aren’t set up right or are blocked, the burning process can be messed up, which can cause the spark to fail. Problems with venting can be caused by bad fitting or by things getting in the way of the venting system.

Problems with the control board: If the electronic control board isn’t working right, the starting process might not work right, which would cause the E003 error code.

How to fix navien error code e003?

Before you try to fix a navien error code e003, you need to make sure you are safe. If you don’t know how to handle the case or don’t feel comfortable doing so, it’s best to call a professional technician. But if you know how to do simple repairs and care, you can follow these steps:

Check Gas Supply: Make sure the gas valve that goes to the water heater is open and that the gas meter and pressure are not broken.

Check the Gas Line: Look at the gas line to see if there are any obvious blocks or barriers. If you think you have a clog, it’s best to let a professional clean it.

Clean Ignition Parts: If you feel comfortable, clean the igniter and flame sensor by following the instructions from the maker. Make sure there is no dirt or dust on the parts.

Check Ventilation: Check the ventilation system for any blockages or bad fitting. The vents should be clear so that air can get in and out properly.

Power cycle: By turning it off, waiting a few minutes, and then turning it back on. This simple step can sometimes fix small problems.

Seek Professional Help: If the problem keeps happening or you don’t know what’s wrong, it’s best to call an experienced navien technician. They have the knowledge and tools to safely figure out what’s wrong and fix it.

Some extra methods to fix navien error code e003

Method 1: Maintain the combustion chamber

  1. The spark plugs and the air filter need to be taken out.
  2. You can use a cleaner and a brush to clean the whole combustion chamber.
  3. Use a dry cloth to clean the room.
  4. Spark plugs and the air filter should be reinstalled.
  5. Check the navien error code 003 after starting the engine.

Still not working? You could:

  • Change out the gas valve
  • Change the valve that lets the air out
  • Change the circuit board

Method 2: Check the flow of the water

  1. Turn the valve backward to turn on the water.
  2. Check to see if the water pressure gauge says “high” or “low.” If the pressure is high, turn the water valve counterclockwise until it says “low.” If the pressure is low, turn the water valve clockwise until it says “high.”
  3. If the water flow still isn’t right, turn the water valve off and then on again. Call a professional if the water flow still doesn’t read right.

Method 3: Remove or clean the inlet filter

  1. Find the input filter by opening the navien machine.
  2. Take out the old filter.
  3. Use a clean cloth to wipe down the filter.
  4. Change the intake filter.

How to fix the most common navien error codes?

If you’re asking why your navien water heater isn’t working even though you’ve reset it more than once, we’re sorry to say that resetting the unit won’t solve all your problems.

There is some good news, though. By looking at the control panel, you can figure out what’s wrong with your heater. If it shows an error code, you can quickly look it up online and find the answer.

On the back of the front cover, you can also find out how to clear the error codes. So, here’s a quick explanation of what the five most common error numbers mean and how to fix them:

  1. Error Code E003

This number means that something went wrong with the ignition.

How to Fix: If you want to fix navien error code e003, you should make sure the following things are true: 1. Make sure the gas is turned on and working correctly. 2. Make sure the unit is getting power and is attached to a power source in the right way. 3. Make sure the ground wire is connected firmly to the right terminal. 4. Make sure the spark is coming from the igniter as it should.

This problem can also happen when the power goes out. If you live in an area where blackouts or power failures happen often, you may need to look into getting a battery backup power supply for your portable water heater.

  1. Error Code E004

This number means that the heater has found a fake flame.

How to Fix: Nine times out of ten, the problem is that the center electrical cord is not properly grounded. Fix that, and the error code will go away.

  1. Error Code E012

This code means that your heater is having trouble with the light going out.

How to Fix: First, check the air entry filter and clean it if it’s dirty. Also, make sure that the center cord is properly connected to the ground.

  1. Error Code E016

This number means that there is a problem with your heater’s heat exchanger getting too hot.

How to Fix: Flushing the heat exchanger and cleaning the filter is the most usual way to get rid of this error code. If the water flows through the heater properly, this won’t happen.

  1. Error Code E030

This number means that the exhaust is too hot. There is also a built-in safety feature that turns off the heater if it gets too hot—149 degrees Fahrenheit or 65 degrees Celsius.

How to Fix: Turn off your heater for at least 30 minutes, then turn it back on. Then, clean out the cold water entry filter, which could be clogged with dirt. You can watch the video here to learn how to clean the water intel filter on your navien tankless water heater. To get rid of this error code from the control panel, you need to clean the heat exchanger.

Customer Care Navien error code e003

You should be able to find their customer service number and help request forms navies to fix error code e003 them. The usual address for the website is

If you live in the U.S., you can also call 1-800-519-8794 to talk to Navien’s U.S. Customer Care for help and advice on how to find authorized service technicians.


Q: What does navien error code e003 mean?

A: The navien error code e003 means that there is a problem with how the water heater is turned on.

Q: What causes Error code e003 most of the time?

A: Some of the most common reasons are not enough gas, a clogged gas line, broken starting parts, problems with venting, or problems with the control board.

Q: Navien error code e003 how to fix?

A: To fix e003, check the gas supply, clean the ignition parts, make sure the venting works, and, if necessary, call an expert.

Q: Is there more than one way to fix error e003?

A: Yes, you can clean the combustion chamber or check the water flow and entrance filter.

Q: What should be done if the navien error code e003 persists despite your troubleshooting efforts?

A: If the problem keeps happening, you should talk to a trained technician for help.


In conclusion, navien error code e003 means that something went wrong when a navien portable water heater was being turned on. This mistake could be caused by a lack of gas, a blocked gas line, dirty or broken ignition parts, problems with the venting, or problems with the control board.

Users can fix error code e003 by doing simple troubleshooting steps like checking the gas supply, cleaning the ignition components, making sure the venting works, and turning the unit off and on again. But if the problem keeps happening or if users aren’t sure what’s wrong, it’s best to get help from a trained technician.

Comment below if you have any questions about how to fix navien error code e003.

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