BoilerFaultCodesYour boiler has detected a fault with an internal temperature monitor and has stopped running as a safety precaution.
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 Replace sensor
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature inside the unit's casing. The most common reason is that the sensor has either burnt out or suffered an electrical failure, but it can also be triggered by a loose or damaged connection in the wiring harness.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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