BoilerFaultCodesYour boiler has detected a critical internal error with its fan or electronic memory and has shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Volatile lockout sensor fan or code plug
What causes this fault?
This fault occurs when the boiler's main computer loses communication with the fan or the small electronic chip that stores the appliance's settings. The most common reason is an electrical failure within the fan motor or a loose connection on the internal circuit board that prevents the boiler from safely managing the airflow. Without this constant data exchange, the system shuts down immediately to prevent an unsafe build-up of gas.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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