BoilerFaultCodesYour boiler's electronic control board has detected a confusing signal from the flame sensor, causing the system 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 detector input signal is outside the limits
What causes this fault?
This fault occurs when the boiler's main control board receives an impossible or conflicting electrical signal from the flame sensing system. The most common reason is an internal electronic failure within the printed circuit board (PCB) itself or a total malfunction of the sensing electrode that monitors the burner.
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 F.67 — 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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