Your boiler detects a flame when it shouldn't, so it has shut down safety to prevent a gas buildup.
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
What causes this fault?
This fault occurs when the boiler's sensors detect a flame after the burner should have switched off or before it has even started. The most common reason is a sensor that has become covered in carbon deposits or has worn out, sending a 'false' signal to the control board. In some cases, a dripping gas valve or a faulty internal circuit board can also make the boiler think a flame is present when it isn't.
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 2 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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