High Lockout
668 on Worcester Bosch WR325 RSF

Your boiler has stopped working because the internal fan, which safely exhausts fumes, is not running correctly.

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

What causes this fault?

This fault occurs when the boiler's safety system detects that the internal fan is either spinning too slowly or has stopped moving entirely. Without a functional fan to pull fresh air in and push exhaust gases out, the boiler will prevent ignition to keep your home safe. The most common reasons are a build-up of debris in the fan motor or a total electrical failure of the fan component.

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

C1View →C6View →A8View →

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