BoilerFaultCodesYour boiler has detected an electrical fault with the internal sensor that monitors the water returning to the unit, causing it to shut down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The contacts of the boiler return temperature sensor have been short circuited
What causes this fault?
This fault occurs when the electrical signals from the sensor monitoring the return water temperature are disrupted, usually because the sensor has failed or become damaged. The most common reason is that the internal components of the sensor have worn out or a leak has caused moisture to corrode the electrical connections. Because the boiler can no longer accurately measure the water temperature coming back from your radiators, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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