BoilerFaultCodesTechnical 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 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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