High Lockout
L8 on Ideal Logic Combi ESP1

Your boiler's internal computer brain either isn't set up correctly or has developed a technical hardware fault, preventing the unit from starting.

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

PCB UNCONFIGURED OR FAULTY

What causes this fault?

This fault occurs when the boiler's main control board has lost its identity and no longer knows which specific model it is supposed to be operating. The most common reason is a technical communication failure between the internal computer chip and the plug-in hardware key that stores the boiler's 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

L2View →F2View →LCView →

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