BoilerFaultCodesYour boiler has detected that a sensor used to monitor water movement has moved out of place or was installed incorrectly, causing the system to stop working 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: Flow sensor: Flow sensor is incorrectly fitted
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring water flow has shifted out of its precise mounting position or has a loose electrical connection. It is usually caused by physical vibration over time weakening the retaining clip or a sensor that was not seated correctly during a recent repair. Because the boiler cannot accurately verify that water is moving, it shuts down to prevent the unit from overheating.
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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