BoilerFaultCodesYour boiler has stopped working because a sensor that monitors the temperature of the water returning to the unit has developed a fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return NTC sensor fault
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors water temperature coming back from your radiators. The most common reason is that the internal components of the sensor have failed due to age or wear, but it can also be caused by loose or damaged electrical wiring. Since the boiler cannot 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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