BoilerFaultCodesYour boiler thinks it sees a flame even though it hasn't tried to light yet, causing it to shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: False Flame Lockout
What causes this fault?
This fault occurs when the boiler's internal sensor detects an electrical signal suggesting a flame is present before the ignition process has even started. The most common reason is a contaminated or damaged flame sensor, though moisture on the internal electronics or a malfunctioning control board can also trick the system into seeing a 'ghost' flame.
This fault can be more frequent during periods of high humidity or heavy rain, as moisture ingress into the flue or dampness within the casing can cause electrical interference with the flame sensing circuit.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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