BoilerFaultCodesYour boiler thinks a flame is present even when it should be turned off, which prevents it from starting up safely.
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 signal
What causes this fault?
This fault occurs when the boiler's sensors detect heat or electricity in the burner area at a time when the gas should be completely shut off. The most common reason is a carbon buildup on the internal probes or a moisture-related fault on the control board, tricking the boiler into thinking a fire is still burning. For safety reasons, the system will prevent the boiler from starting any new heating cycle until this is resolved.
This fault can be more frequent during periods of high humidity or heavy rain, as moisture ingress into the air intake can affect the sensitivity of the ignition components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E2 — no call-out fees, no surprises.
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