High
15 on Alpha Evoke 10 / 18

Your boiler’s internal computer is confused because its software settings do not match the physical parts installed, causing the system to stop working for safety.

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 hydraulic 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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