High
Red lockout light on Ferroli F 30 B

Your boiler has detected an issue and stopped working as a safety precaution, likely because the fuel supply is interrupted or the internal pipe for water drainage is blocked.

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

Boiler lock out - check gas supply or condensate discharge

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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