High Lockout
C1264 on Worcester Bosch CDi Classic

Your boiler's fan has unexpectedly stopped working while the unit was running, causing the system to shut down for safety.

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

Fan stopped during operation

What causes this fault?

This fault occurs when the boiler's control system loses the signal from the fan while it should be spinning to clear exhaust gases. It is usually caused by the fan motor burning out, a loose connection in the internal wiring, or a fault on the main circuit board failing to provide power to the unit.

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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Related fault codes

C6View →

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