How much does it cost to fix boiler error code Lock lamp on?

Typical repair cost for the boiler Lock lamp on fault is £120-300 including labour.

Lock lamp on High

Boiler Fault Code Lock lamp on

Also written as LOCKLAMPON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Lock lamp on 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 is failing to light the gas even though it is trying to spark, causing the system to shut down for safety. (As reported on Biasi Aquapiu 2002)

Pick your boiler brand for the Lock lamp on fix

Biasi Lock lamp on 1 model

Source

Information for the Lock lamp on 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