BoilerFaultCodesYour boiler's computer brain has encountered a serious internal error 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: Internal control fault
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure and loses the ability to process instructions or monitor safety sensors. It is typically caused by electrical degradation of the components on the circuit board or a loose connection in the internal wiring. Because the 'brain' can no longer guarantee the boiler is operating safely, it shuts the entire system down as a precaution.
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 E15 — no call-out fees, no surprises.
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