There are a large number of unique Navien error codes that help with troubleshooting the issue. Some problems can be solved with simply resetting the water heater unit (press the Reset button on the front panel) but other require more work.
Below you’ll find the most common error codes for a Navien tankless water heater along with a suggested fix. Often, you can complete simple fixes on your own with a few tools but for some more complex problems, you’ll need to contact a professional plumber who is familiar with Navien models or go straight to the manufacturer for support.
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