BoilerFaultCodesTechnical description
If the boiler does not light after 3 attempts the fault code LF will be displayed (Ignition lockout).
What causes this fault?
This fault occurs when the boiler's control system senses that a flame has not been established after several attempts to start. The most common reasons include a lack of gas reaching the burner, a faulty spark electrode failing to light the gas, or a sensor that cannot detect the flame even if it has lit.
This fault is more frequent during extreme cold spells, as external gas meters or pipes can freeze, restricting the gas flow required for ignition.
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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