How much does it cost to fix boiler error code lock-out light?

Typical repair cost for the boiler lock-out light fault is £100-350 including labour.

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Boiler Fault Code lock-out light

Also written as LOCKOUTLIGHT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code lock-out light appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has shut down for safety because it either failed to light, sensed it was getting too hot, or detected an issue with how it clears waste gases. (As reported on Biasi Garda M90f)

Pick your boiler brand for the lock-out light fix

Biasi lock-out light 1 model

Source

Information for the lock-out light fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026