High Lockout
FE97 on Alpha Pro Tec Plus

Your boiler's internal computer system is currently confused and cannot communicate correctly, meaning the unit will not start until it is digitally reconfigured.

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

Boiler PCB configuration error. This may occur if the main PCB or display PCB is changed.

What causes this fault?

This fault occurs when the boiler's internal control boards fail to recognise each other or have conflicting information about how the unit should operate. The most common reason is that a replacement part has been installed but not correctly programmed to match your specific model, or a surge in the electrical supply has scrambled the memory on the circuit board.

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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