High
Lock-out signal lamp ON on Biasi Riva Compact 24S

Your boiler is failing to detect the flame after lighting, causing it to shut down for safety purposes even though the gas is ignited.

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

The burner doesn't light, the ignition sparks continue and the boiler locks. By pressing the reset push-button the boiler starts the ignition cycle. The burner lights, the ignition sparks continue and the boiler locks again.

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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