BoilerFaultCodesYour boiler has detected an internal electrical problem or a grounding issue that is preventing it from running safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control unit or earth fault
What causes this fault?
This fault occurs when the boiler's main computer loses its ability to correctly monitor the electrical circuit or detects a leak of electricity to the ground. The most common reason is a component failure within the control board itself or a loose connection in the internal wiring that breaks the safety loop. In some cases, a worn-out ignition electrode can also interfere with the unit's electrical signals.
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 é3 — no call-out fees, no surprises.
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