High
Lockout flame signal on Halstead Finest 80

Your boiler is failing to ignite or stay lit because it cannot detect a flame, meaning you currently have no heating or hot water.

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

No flame signal on ignition, or loss of signal during operation • Check detection electrode/lead • Check gas supply • Check gas valve and lead • Check PCB/spark generator

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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