BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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