BoilerFaultCodesYour boiler's computer brain has encountered a serious internal software or hardware glitch and cannot function.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal electronics error – rest or replace control box
What causes this fault?
This fault occurs when the boiler's main control board experiences a critical communication failure or an internal memory error. It is usually caused by an electrical component failure on the circuit board or a corruption in the system's software that prevents it from managing the heating safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E11 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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