Navien error codes
The complete list of Navien fault codes shown on the display, each with what it means and the page that explains how it is diagnosed and fixed.
Navien heating appliances display 38 documented error codes. Each code below opens its own page with the official meaning, the documented causes, the safety assessment and the parts involved.
All Navien Error Codes
38 codes, each with its own page. Click a code to open the meaning, the documented causes and the repair.
What Fails Most Often on Navien
Grouped from the official meaning of each of the 38 codes above — not from opinion. The number is how many different fault codes point at that component.
| Component | Codes | Examples |
|---|---|---|
| Temperature Sensor | 12 | 218, 421, E144, E205 |
| Water Pressure | 3 | E302, E352, E353 |
| Communication | 3 | E736, E782, E784 |
| Overheat | 2 | E001, E031 |
| Ignition | 2 | E003, E012 |
| Heat Exchanger | 2 | E016, E046 |
| Fan | 2 | E109, H320 |
Parts & Prices
The parts most often involved in the Navien faults listed above.
Prices and availability vary by region and are shown by the retailer, not by TroubleAtlas.
Diagnostic Tools
What an engineer uses to work through the codes on this page.
TroubleAtlas Score — Navien
How Navien scores
Independently assessed across six dimensions from the documentation, the fault codes and the parts network. Based on 100 error codes across 34 appliances.
How we calculate it →TroubleAtlas Pro
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Considering a New Heating System?
If your Navien appliance is over 10 years old, replacing it with a modern condensing boiler or air-source heat pump could cut energy bills and remove the recurring faults listed on this page.
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