BoilerFaultCodesYour boiler has detected an electrical issue with the pipe sensor that monitors water returning to the unit, causing it to shut down for safety.
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 short circuit
What causes this fault?
This fault occurs when the electrical signal from the sensor that monitors water coming back into the boiler is interrupted, usually by a broken internal wire or a component failure. The most common reason is that the sensor itself has developed a short circuit, meaning it can no longer send accurate temperature readings to the main control board. Because the boiler cannot safely monitor its own operation without this data, it shuts down to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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