BoilerFaultCodesYour boiler has detected a problem with the sensor that measures the temperature of the water leaving the unit, causing it to shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow heating thermistor fault
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of the water being sent to your radiators. The most common reason is that the sensor has electronically failed or the internal wiring connecting it to the control board has become loose or damaged. Because the boiler no longer knows how hot the water is, it shuts down to prevent the system 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 F10 — no call-out fees, no surprises.
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