BoilerFaultCodesYour boiler has stopped working because it can no longer accurately measure the temperature of the water inside the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water Temperature Sensor fault - The sensor is either short circuit or open circuit.
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring water temperature fails to send a clear signal to the boiler's control board. The most common reason is that the sensor's internal electrical resistance has broken down over time, or the wiring connecting it has become loose or damaged. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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