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

Book a service

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

What the manual says

Manufacturer manual

Abnormal operation: DHW circulation

From this model's manual
Verified against the Navien Ncb installation & service manual, page 74.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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