BoilerFaultCodesYour boiler is failing to detect a flame when it tries to fire up, so it has 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 detection fault
What causes this fault?
This fault occurs when the boiler's control system cannot confirm that a flame has successfully lit within the combustion chamber. The most common reasons are a worn-out sensor that can no longer 'see' the flame or a fault within the internal electronics that prevents the signal from reaching the main control board.
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.
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A boiler cover plan would cover faults like F16 — no call-out fees, no surprises.
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