BoilerFaultCodesYour boiler has lost communication with the internal thermometer that monitors water temperature, causing the system 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 temperature sensor disconnected
What causes this fault?
This fault occurs when the boiler's main computer can no longer detect a signal from the sensor that monitors how hot the water is getting. It is usually caused by the sensor failing internally due to age, or a loose connection in the internal wiring that has broken the electrical circuit. Because the boiler cannot safely monitor its own temperature, 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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