BoilerFaultCodesYour boiler is unable to create the spark needed to light the gas burner, meaning the system cannot fire up to provide heat.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Subsequent display screens would direct attention to the spark generator if HT generator ceases to function
What causes this fault?
This fault occurs when the internal electronic component responsible for creating a high-voltage pulse fails to deliver power to the burner. The most common reasons are the electronic spark box burning out internally or the ignition electrodes becoming worn and soot-covered over time. Without this electrical arc, the gas won't ignite, and the boiler shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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