Medium
E792 on Navien NCB

Your boiler is struggling to pump hot water through the internal system correctly, which may cause your hot water to fluctuate or fail to reach your taps.

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: DHW circulation

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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