BoilerFaultCodesYour boiler's internal sensor that monitors exhaust gases has developed a fault, 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 NTC Fault
What causes this fault?
This fault occurs when the boiler's internal safety sensor detects that the exhaust gases are too hot or if the sensor itself has suffered an electrical failure. Over time, the sensor can degrade due to constant exposure to heat, or the wiring connecting it to the main control board may have become loose or damaged. Because this component monitors high temperatures, the boiler shuts down immediately to prevent any internal damage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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