BoilerFaultCodesYour boiler has detected an electrical fault with the sensor that monitors exhaust gases, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue sensor short circuit – check connections to flue sensor
What causes this fault?
This fault occurs when the electrical signal from the exhaust gas sensor becomes interrupted, usually because the component has failed internally or the wiring has become damaged. The sensor is designed to monitor the temperature of the fumes leaving your home, and if it detects an electrical short, the boiler will shut down immediately to prevent potential overheating or safety risks.
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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