High
Lock state on Biasi Prisma

Your boiler has shut down completely for safety because it failed to light or stay lit after several attempts.

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 ignition device can lock the functioning of the boiler and stop its functioning up to the resetting intervention. The lock is signalled by the ignition of the lock lamp.

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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