BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors the water temperature, causing the system to shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Primary temperature sensor (NTC) fault
What causes this fault?
This fault occurs when the sensor responsible for monitoring the heat of the water inside the boiler fails or sends an incorrect signal. 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 track temperature. Because the system doesn't know how hot the water is, it shuts down to prevent the unit from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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