High
FAIL POINT H / Burner Lockout on Worcester Bosch 24/28CDi II RSF

Your boiler is not starting because it cannot successfully ignite the gas flame to heat your water.

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

Flashing slow - Gas supply, electrode/ignition, gas valve, or flame sensor fault

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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