BoilerFaultCodesTechnical description
Burner does not fully ignite / 230V at pin 3 of terminal X15 (Right white wire) or pin 2 of terminal X15 (Left white wire)
What causes this fault?
This fault occurs when the boiler's control system attempts to start the heating process but fails to detect a sustained flame. The most common reason is that the gas valve isn't opening correctly to deliver fuel, or the ignition system is failing to provide the spark needed to light the burner. As a safety precaution, the boiler stops trying to fire to prevent unburned gas from building up.
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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