High
Lockout lamp (red) on on Biasi Prisma

Your boiler has stopped working for safety reasons and needs to be manually restarted to try and 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

The boiler has failed to ignite or has detected a safety fault. Manual intervention via the reset push-button is required.

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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