High
lock-out signal lamp on Biasi Riva Compact HE M96a

Your boiler has stopped working for safety reasons and needs to be manually restarted to attempt to fire up again.

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

Electronic control/ignition p.c.b. can lock the functioning of the boiler (lock state). The lock is signalled by the lighting of the lock-out signal lamp and the device can be reset only by using the boiler reset button.

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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