BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors water returning to the unit, meaning it cannot safely regulate the temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return sensor fault – sensor wiring shorted or broken – check the wiring
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of the water returning from your radiators. This is usually caused by the sensor's internal components failing due to age or the electrical wiring becoming loose or damaged. Because the boiler cannot accurately measure the water temperature, 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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