BoilerFaultCodesTechnical description
Replace control board
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure or a memory error, meaning it can no longer process data or send instructions to parts like the pump or fan. The most common reasons for this are age-related component wear or an electrical surge that has damaged the delicate circuitry inside the control box.
This fault is often seen after summer storms or during the first cold snap of winter, as electrical spikes from lightning or the sudden strain of restarting the heating can push a failing circuit board to the point of collapse.
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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