BoilerFaultCodesYour boiler has detected that a temperature sensor is not working correctly, meaning it cannot accurately measure how hot the water is.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault on Temperature Sensor
What causes this fault?
This fault occurs when the boiler's control board loses communication with the internal temperature sensor, often because the component has suffered electrical failure or chemical degradation over time. The most common reason is that the sensor has become 'scaled up' or the internal thermistor has worn out, preventing it from sending a reliable signal to the boiler.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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