BoilerFaultCodesYour boiler has stopped working because its internal computer system has detected an electrical communication problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal fault
What causes this fault?
This fault occurs when the boiler's main control board fails to communicate correctly with the internal sensors and components. The most common reason is a physical failure of the electronic circuit board or a loose connection in the internal wiring loom that prevents signals from being sent. Because the 'brain' of the boiler cannot verify that it is safe to operate, it shuts down the system entirely.
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 E5 — no call-out fees, no surprises.
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