BoilerFaultCodesYour boiler has detected a problem with the internal ignition components, meaning it cannot safely light the burner to provide heat or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault: Electrodes. Electrodes not connected or they are connected incorrectly, short circuit in the cable harness
What causes this fault?
This fault occurs when the boiler's control board loses communication with the components responsible for creating the spark and sensing the flame. It is usually caused by a loose connection, damaged wiring, or electrodes that have worn down and can no longer complete the electrical circuit required to start the boiler. Without this secure connection, the system shuts down as a safety precaution to prevent unburnt gas from entering the combustion chamber.
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 F.87 — 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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