BoilerFaultCodesTechnical description
Number of unsuccessful lockouts
What causes this fault?
This fault occurs when the boiler has repeatedly failed to light or detect a flame, causing the system to lock itself out for safety after five unsuccessful attempts. It is usually caused by a lack of gas supply, a worn-out ignition spark, or a component failure that prevents the burner from sustaining a flame.
This issue is more frequent during the first cold snap of winter when components that have been idle all summer are suddenly under high demand and fail to cooperate.
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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