High
L 8 on Ideal Isar HE

Your boiler has detected that the internal mechanism responsible for clearing waste gases is not spinning correctly, so it has safely shut down to prevent any unsafe operation.

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

ALTERNATING 'L' '8' GO TO FRAME 89

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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