BoilerFaultCodesTechnical description
LOCKOUT
What causes this fault?
This fault occurs when the boiler tries to light but fails to detect a stable flame after several attempts. The most common reasons are a lack of gas supply to the appliance, a worn-out ignition spark, or a faulty sensor that cannot 'see' the flame even if it has lit.
This fault is more common during extreme cold snaps, as freezing temperatures can cause the external condensate pipe to block, preventing the boiler from completing its ignition cycle.
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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