BoilerFaultCodesYour boiler has detected a problem with an internal sensor that monitors the main casing, which has stopped it from running safely for now.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Case sensor Sensor failed open or closed circuit
What causes this fault?
This fault occurs when the boiler's control system loses communication with the sensor that monitors the temperature inside the main unit. It is usually caused by the sensor's internal components failing due to age, or the electrical wiring connecting it to the main circuit board becoming loose or damaged. To prevent overheating or unsafe operation, the boiler automatically shuts down until the sensor can provide a reliable reading.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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