BoilerFaultCodesYour boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water 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 NTC short circuit
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of the water leaving your boiler develops an electrical short circuit. The most common reason is a component failure within the sensor itself or moisture ingress that has damaged the internal wiring. Because the boiler can no longer safely monitor 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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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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