Worcester Bosch Ignition lockout Fault Code
Also written as IGNITIONLOCKOUT — same fault.
The Worcester Bosch Ignition lockout fault code means: your boiler has stopped working because it failed to light the flame, which means your heating and hot water have turned off for safety.. It appears on 3 Worcester Bosch models in our database.
Technical description: The fault indicator will flash slowly (approximately once per second). The burner fails to light after 5 attempts and the electricity supply to the gas valve is interrupted.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Worcester Bosch models that show the Ignition lockout fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch Ignition lockout fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026