BoilerFaultCodesTechnical description
Flame simulation
What causes this fault?
This fault occurs when the boiler's sensors detect a flame signal at the wrong time, specifically before the ignition process has even started. The most common reasons are a faulty sensor sending a false signal or a component like the control board malfunctioning and 'hallucinating' a flame, which triggers an immediate shutdown for safety.
This fault can be more common during periods of high humidity or after heavy rain, as moisture ingress into the casing can interfere with the sensitive electrical signals of the flame detection circuit.
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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