BoilerFaultCodesYour boiler's internal computer has suffered a technical failure and is unable to control the heating process.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal failure - electronic
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware malfunction, preventing it from processing instructions or safety checks. The most common reason is a component failure within the circuitry, often caused by age or a power surge that disrupts the board's internal communication.
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 411 — no call-out fees, no surprises.
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