BoilerFaultCodesTechnical 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 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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