High
Burner Lockout on Worcester Bosch 24CDi BF

Your boiler is failing to ignite the flame needed to produce heat or hot water, so it has purposefully shut itself down for safety.

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

Burner fails to light or maintain flame. Checks: Gas supply/pressure, spark electrode/gap, HT leads, and flame sensing.

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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