BoilerFaultCodesYour boiler has detected a problem with the sensor that monitors hot water temperature, which may result in no hot water or inconsistent temperatures.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: DHW thermistor fault
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of your tap water fails to send a consistent signal to the boiler’s control board. The most common reason is that the sensor has physically degraded over time or developed an internal electrical short, preventing the boiler from knowing how hot the water is. In some cases, it can also be triggered by loose or corroded wiring connections between the sensor and the main computer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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