High
L 8 on Ideal Mexico Super 100FF / 125FF

Your boiler has detected a critical internal error that prevents it from starting, which typically requires a qualified gas engineer to inspect the control systems and electrical connections.

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

GO TO FRAME 73

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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