High
23 on Alpha E-Tec Plus

Your boiler's computer is confused because it has detected a mismatch in its internal settings, meaning it cannot safely start your heating or hot water.

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

Incorrect configuration - There is an inconsistency between the settings and signals received from the PCB

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

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