High Lockout
PCB REPLACED on Ideal Logic Max Combi

Your boiler has recently had its main circuit board changed and simply needs a quick reset to finish the setup process.

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

Restart boiler by pressing RESTART

What causes this fault?

This message appears because the boiler’s main control board has been replaced and requires a final confirmation to synchronise with the rest of the components. It is a built-in safety step to ensure the new part is recognised correctly before the boiler begins its normal heating cycle. Once you press the restart button, the system will clear this notification and resume operation.

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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