BoilerFaultCodesYour boiler thinks there is still a flame burning even though it has commanded the system to turn off, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame detected although burner is switched off
What causes this fault?
This fault occurs when the boiler's control system senses an electrical signal from the burner area at a time when there should be no fire present. The most common reason is a contaminated or damaged sensing electrode sending a false signal, or a fault within the main circuit board incorrectly interpreting electrical noise as a flame.
This fault can occasionally be triggered by high humidity or heavy rain, as moisture ingress into the flue or internal components can cause the electrical tracking that leads to a false flame signal.
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 F7 — no call-out fees, no surprises.
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Could it be time for a new boiler?
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