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

Your boiler has detected a failure to ignite or a loss of flame during operation, and it has safely locked itself out to prevent gas buildup.

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 72

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

L 9View →

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