Medium
E787 on Navien NCB

Your boiler has detected a temporary internal memory or logic error and needs to be restarted to clear the fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Abnormal operation: Reset device

DIY fix possible

Locate the 'Reset' button on the boiler control panelPress and hold the button for 3 to 5 secondsWait 5 minutes while the boiler restarts and attempts to reignite

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