BoilerFaultCodesYour boiler has detected a problem with its internal temperature sensor and has stopped working 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: Thermistor error
What causes this fault?
This fault occurs when the boiler's internal temperature sensor, known as a thermistor, fails to send a reliable signal to the main control board. The most common reason is that the sensor has developed an electrical fault or has simply worn out over time, meaning it can no longer accurately monitor the water temperature. As a result, the boiler shuts down to prevent itself from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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