BoilerFaultCodesYour boiler thinks a flame is still burning inside the unit even though it has been told to turn off.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Flame detected even if boiler switched off
What causes this fault?
This fault occurs when the boiler's sensors continue to detect heat or electrical signals from a flame after the heating cycle has finished. The most common reason is that the gas valve has failed to close fully or the sensing probe is sending a false signal to the internal computer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F7 — no call-out fees, no surprises.
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Worcester Bosch Highflow 400 BF is discontinued — time for a new one?
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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