BoilerFaultCodesYour boiler has stopped working because it cannot correctly measure the temperature of the water returning from your radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return temperature sensor failed
What causes this fault?
This fault occurs when the boiler's internal computer stops receiving a reliable signal from the component that monitors water temperature coming back from your heating system. The most common reason is that the sensor has electronically failed or 'drifted' out of its safe operating range, though it can also be caused by a loose connection or damaged wiring. Because the boiler can no longer safely monitor its own temperature, it shuts down to prevent potential overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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