BoilerFaultCodesTechnical description
Appliance does not light & goes to lockout
What causes this fault?
This fault occurs when the boiler's control system attempts to light the burner but fails to detect a flame after several attempts. The most common reasons include a lack of gas reaching the unit, a worn-out component failing to create a spark, or a sensor that can no longer confirm the flame is safely lit.
This fault is more frequent during the first cold snap of winter, as gas valves can occasionally stick after being inactive during the summer months.
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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