BoilerFaultCodesYour boiler has identified a communication problem with the sensor that monitors water returning from your radiators, preventing the system from operating correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Open circuit on return sensor
What causes this fault?
This fault occurs when the boiler's main control board loses its connection with the sensor that measures the temperature of water returning from the radiators. The most common reason is that the internal components of the sensor have failed, or the electrical wiring connecting it to the brain of the boiler has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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