BoilerFaultCodesYour boiler's internal computer has developed a fault and can no longer control the system safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main PCB fault
What causes this fault?
This fault occurs when the main control board's internal memory or processor fails, meaning it can no longer communicate with the boiler's sensors or valves. The most common reason is electrical fatigue or a power surge that has damaged the delicate circuitry on the board. Over time, heat exposure within the boiler casing can also cause the soldered connections on the PCB to degrade and fail.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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