BoilerFaultCodesYour boiler is unable to create the electric spark needed to light the gas burner, meaning your heating and hot water will not work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Spark Generator Fault: Check wiring, if OK replace spark generator
What causes this fault?
This fault occurs when the boiler's internal electronic starter fails to send a high-voltage charge to the ignition probes. The root cause is usually a breakdown in the spark generator’s internal circuitry or a loose connection that prevents the electrical arc from jumping across the burners to light the gas. In some cases, the control board may be failing to send the initial command signal to begin the ignition process.
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 F10 — 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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