High
E517 on Navien NCB

Your boiler has detected an incorrect configuration setting on its internal computer, which is preventing it from starting up correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Abnormal operation: DIP switch setting (PCB)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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