BoilerFaultCodesYour boiler has shut down because it can no longer safely monitor the temperature of the exhaust gases leaving the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue gas temperature sensor open circut
What causes this fault?
This fault occurs when the boiler's internal computer loses its connection to the sensor that monitors the heat of the exhaust gases. The most common reason is that the sensor itself has suffered an internal electrical failure or the wiring connecting it to the main control board has become loose or damaged. Because the boiler can no longer verify that it isn't overheating the flue system, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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