High Lockout
L09 on Ideal Logic Max Combi

Your boiler's internal computer brain is not communicating correctly with the rest of the unit and needs to be officially set up.

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

Unconfigured PCB

What causes this fault?

This fault occurs when the boiler's main control board has lost its identity or was never properly told which specific model it is installed in. The most common reason is that a new circuit board has been fitted but not yet programmed with the correct software code, or a sudden power surge has wiped the board's internal memory.

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

L01View →L02View →LCView →

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