BoilerFaultCodesYour boiler has stopped working because it cannot accurately 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 sensor: Sensor failed open or closed circuit
What causes this fault?
This fault occurs when the internal computer can no longer detect a signal from the sensor that monitors water temperature coming back from your radiators. The most common reason is that the sensor's internal component has burnt out or cracked, though it can also be caused by loose or corroded electrical wiring connecting the sensor to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 6 — no call-out fees, no surprises.
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