High Lockout
F9 on Ideal Logic Max Combi

Your boiler’s internal control board has lost its configuration or is brand new and hasn't been programmed yet to tell it which model it is.

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

Unprogrammed PCB / PCB replacement mode

What causes this fault?

This fault occurs when the boiler's central brain loses the specific instructions that tell it how to operate your particular heating system. It is most commonly caused by a power surge that has wiped the memory chip, or it appears after a technician has installed a brand new control board that hasn't been configured yet.

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

L9View →F2View →L2View →

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