High
E46 on Keston System S40

Your boiler's main control board is unable to talk to the display panel on the front, meaning the system cannot carry out your instructions.

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

Communication error between fascia and control box – check cables

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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Related fault codes

E40View →E43View →

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