BoilerFaultCodesYour boiler has stopped working because one of its internal sensors has developed an electrical fault and can no longer measure the temperature of the water leaving the unit.
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 electrical connection within the flow temperature sensor fails, causing it to send an incorrect signal to the main control board. The most common reason is that the sensor has developed an internal short circuit due to age, or moisture has compromised the wiring connections. Because the boiler can no longer safely monitor how hot the water is, it shuts down as a safety precaution.
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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