BoilerFaultCodesYour boiler's internal computer has developed a fault and can no longer control the heating 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 board fault
What causes this fault?
This fault occurs when the boiler's central control unit suffers an internal electrical failure or memory error. It is typically caused by ageing capacitors on the circuit board or sudden electrical surges that damage the delicate microprocessors. Because the 'brain' of the boiler can no longer communicate with the sensors and gas valve, the unit shuts down to prevent unsafe operation.
This fault is slightly more common during winter months when the boiler is working under high demand or following heavy thunderstorms which can cause electrical spikes in the local grid.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 13 — no call-out fees, no surprises.
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