High
Lock-out signal lamp red on Biasi Riva Plus M96.24SM

Your boiler is trying to start but cannot light the gas flame, causing it to shut 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

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