BoilerFaultCodesYour boiler has detected an electrical fault with the internal sensor that monitors the water temperature leaving the unit, causing it 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: Flow temperature sensor short circuit
What causes this fault?
This fault occurs when the electrical connection to the flow sensor is interrupted, usually by a short circuit in the sensor itself or the internal wiring. This is often caused by moisture ingress from a small leak or natural wear and tear to the electrical components over time. Because the boiler can no longer safely track how hot the water is, it shuts down to prevent 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 F.10 — no call-out fees, no surprises.
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