High
L A (flashing) on Ideal Icos

Your boiler has switched itself off because it has detected an unsafe build-up of heat, requiring a professional to check for internal circulation or sensor issues.

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

Boiler is not working for central heating or hot water and the display shows ‘L A’ (flashing). If fault recurs this indicates an overheat condition.

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 FView →

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