BoilerFaultCodesTechnical description
Flame lockout
What causes this fault?
This fault occurs when the boiler attempts to start up but cannot detect a sustained flame, leading it to shut down for your safety. The most common reasons include a lack of gas reaching the unit, worn-out spark electrodes that can no longer ignite the fuel, or a faulty sensor that fails to 'see' the flame even if it is lit.
This issue can be more frequent during extreme cold spells if the external gas regulator freezes or if damp weather affects the electrical integrity of the ignition leads.
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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