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 is no longer able to process signals or manage safety checks. The most common reason is that age and electrical wear have caused the internal components of the circuit board to degrade or short-circuit. Because the brain of the boiler can no longer verify it is operating safely, it shuts down the system entirely as a protective measure.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like E11 — no call-out fees, no surprises.
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