BoilerFaultCodesYour boiler has stopped working because the internal fan, which safely exhausts gases, is unable to start or spin at the correct speed.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Lights: Flash Flash On. NOTE: The fan is supplied with 325 Vdc. Check continuity from N to O & from P to Q on 3-way PCB connector. Check continuity from R to S & from T to U & from V to W on smaller 6-way PCB connector.
What causes this fault?
This fault occurs when the boiler's control board cannot detect the fan spinning at the speed required to safely clear waste gases from the system. The most common physical causes are a buildup of dirt or debris in the fan blades, a complete motor failure, or a loose electrical connection between the fan and the main circuit board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like FAN LOCKOUT — no call-out fees, no surprises.
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