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

Typical repair cost for the boiler Light on fault is £100-280 including labour.

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Boiler Fault Code Light on

Also written as LIGHTON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Light on appears across 1 boiler brand and 12 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is receiving power and trying to work, but it has failed to start the burner to provide heat or hot water. (As reported on Worcester Bosch Greenstar Ri)

Pick your boiler brand for the Light on fix

Worcester Bosch Light on 12 models

Source

Information for the Light 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