High
E.782 on Navien NCB 35 HE

Your boiler's main control unit and the display panel are having trouble 'talking' to each other, which prevents the system from operating 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

Panel communication error (Level 1). Displayed when the controller does not respond for more than 60 sec or whenever a panel communication error occurs regardless of the error level.

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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