BoilerFaultCodesTechnical description
Case temperature sensor fault (open or short circuit)
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that prevents the outer casing from overheating. It is usually caused by the sensor failing due to age, or a loose electrical connection within the wiring harness that has been shaken or worn over time. For safety, the boiler shuts down immediately because it can no longer verify that the unit is operating at a safe external temperature.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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