Navien · Combi boiler
E517 DIP switch setting fault
What the control is telling you
The DIP switch settings are invalid or inconsistent. NFC-H manual lists the reset type as: Manual reset.
Applies to: Navien fire-tube combi boilers, NFC-H series (NFC-250/200H, NFC-250/175H) and NCB-H combi boilers (NCB-250/150H, NCB-240/130H, NCB-240/110H, NCB-190/080H, NCB-190/060H)
Likely causes
- DIP switch set to an unused combination
- NFC-H: model DIP switches SW1 5&6 not matching the model
Test and repair steps
- Warning: turn power off before touching the DIP switches.
- Check DIP SW1 and SW2 against the DIP switch tables (SW1 1&2 OFF/OFF for normal operation; SW2 5&6 OFF/OFF for US/Canada).
- NFC-H SW1 5&6 = OFF/OFF for NFC-250/200H, ON/OFF for NFC-250/175H.
- Code keeps returning? Phone Navien Technical Support, 1-800-519-8794.
Settings for these units
- Minimum installation clearances (indoor) · Navien NCB-H
- Water quality limits (DHW and system fill) · Navien NCB-H
- Minimum installation clearances (indoor) · Navien NFC-H
- Water quality limits (DHW and system fill) · Navien NFC-H
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Source: Navien NCB-H Installation & Operation Manual, 11.7 Understanding Error Codes, p.129-130; Navien NFC-H Installation Manual, 11.7 Understanding Error Codes, p.127-128. Summarized in our own words; check the original manual for your model.
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