High Lockout
Spare PCB Not Set on Ideal Logic Max Combi

Your boiler's main control board has been replaced or reset but hasn't been programmed with the specific settings required to run your heating and 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

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What causes this fault?

This fault occurs when a newly installed circuit board or one that has been reset does not yet know which specific boiler model it is controlling. Because the same board is used across several different models, it remains in a standby state until an engineer enters a unique code to activate the correct heating and hot water settings.

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

F1View →L2View →FNView →

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