BoilerFaultCodesYour boiler is still sensing a flame even when it should be turned off, which is a safety conflict that prevents the system from starting.
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 even though appliance is switched off.
What causes this fault?
This fault occurs when the boiler's internal sensor mistakenly reports that a flame is present in the burner after the heating cycle has finished. The most common cause is a dirty or damaged sensing probe that is sending a false signal, or a fault within the main control board that is misinterpreting the data. For safety reasons, the boiler identifies this as a conflict and will refuse to ignite to prevent any potential over-heating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F7 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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