BoilerFaultCodesYour boiler has detected a sensor failure and has stopped working to prevent incorrect water temperatures.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: NTC thermistor fault
What causes this fault?
This fault occurs when the boiler's internal temperature sensors stop communicating correctly with the main control board. The most common reason is that the sensor has physically degraded over time or developed an electrical short, meaning the boiler can no longer safely monitor how hot the water is getting. In some cases, it can also be triggered by loose or corroded wiring connections between the sensor and the brain of the boiler.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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