BoilerFaultCodesYour boiler has detected a technical 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
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of the exhaust gases sends an incorrect electrical signal to the boiler's brain. The most common reason is that the sensor has suffered an internal electrical failure or the connecting wires have become damaged or loose. Because the boiler can no longer safely monitor heat levels in the flue, it shuts down immediately to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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