Medium
E787 on Navien NCB H

Your boiler has detected a minor internal software or communication glitch and needs to be restarted to clear the error.

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 power switch or the fuse spur supplying the boiler.Turn the boiler power off and wait for at least 60 seconds.Turn the power back on and see if the error code clears itself.

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Related fault codes

E786View →E788View →

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