BoilerFaultCodesTechnical description
Hot water NTC (Negative Temperature Coefficient) error
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring your hot water temperature fails or sends an incorrect signal to the main control board. The most common reason is that the sensor has physically degraded over time or developed a short circuit, meaning the boiler can no longer safely verify how hot the water is. Occasionally, loose or damaged wiring between the sensor and the boiler’s computer can also trigger this shutdown.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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