BoilerFaultCodesYour boiler has detected that the internal fan is spinning too slowly to safely clear waste gases, so it has shut down as a precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan speed too low
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is not reaching the required speed to safely expel exhaust fumes. The most common reasons are a buildup of dirt inside the fan housing, electrical components on the fan failing, or a fault within the main circuit board that prevents it from sending the correct power to the motor.
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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