BoilerFaultCodesYour boiler is struggling to start up properly because the main internal computer is failing to control the fan correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty printed circuit board
What causes this fault?
This fault occurs when the boiler's main control board loses the ability to communicate properly with the fan motor, leading to erratic speeds or 'hunting' for the correct setting. The most common reason is that the electrical components on the circuit board have degraded over time, meaning it can no longer send a steady signal to keep the fan running safely.
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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