BoilerFaultCodesTechnical description
Ignition lockout error
What causes this fault?
This fault occurs when the boiler's control system attempts to light the burner multiple times but fails to detect a stable flame. The most common reasons include a worn-out ignition spark, a faulty gas valve that isn't opening properly, or an issue with the sensor that confirms the fire is actually lit.
This issue is slightly more frequent in winter as cold weather can affect gas pressure and put older, struggling ignition components under more strain.
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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