BoilerFaultCodesYour boiler has stopped working because it has lost the electrical connection to its temperature sensor.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Open circuit between PCB terminals 23-24
What causes this fault?
This fault occurs when the boiler's main control board loses the electrical signal from the flow thermistor, which is the component that monitors water temperature. The most common reason is a physical break in the internal wiring or a sensor that has reached the end of its life and can no longer transmit data. Without this reading, the boiler shuts down as a safety precaution because it cannot tell if the water is getting too hot.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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