BoilerFaultCodesYour boiler is failing to light the gas flame, 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: Check gap at electrode, integrity of electrode and lead, and PCB connections
What causes this fault?
This fault occurs when the boiler's control system attempts to start a flame but cannot generate the necessary spark to ignite the gas. The most common reasons are a cracked ceramic insulator on the spark plug, a loose connection in the wiring, or the internal control board failing to send power to the ignition system.
This issue is frequently seen after a long summer break when the boiler is first turned back on for autumn, as moisture or debris can settle on the electrode during periods of disuse.
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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A boiler cover plan would cover faults like No spark at ignition electrode — no call-out fees, no surprises.
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