BoilerFaultCodesYour boiler has stopped working because a sensor that monitors water temperature has lost its connection or stopped sending a signal.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The Flow NTC (Negative Temperature Coefficient Thermistor) cable is either defective or broken and needs to be replaced
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the sensor that monitors the temperature of the water leaving the unit. The most common reasons are an electrical failure within the sensor itself or a break in the wiring caused by vibration, heat exposure, or moisture. Without this data, the boiler shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F.01 — no call-out fees, no surprises.
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