High
Lock-out signal lamp red (ON) on Biasi Riva Compact HE M96a

Your boiler is failing to detect the flame after lighting, causing it to shut down for safety even though the burner briefly ignites.

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 up, the ignition sparks continue and the boiler blocks. Pressing the reset push-button the boiler starts the ignition cycle again. The burner lights up, the ignition sparks continue and the boiler blocks 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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