BoilerFaultCodesYour boiler has detected a fault with its temperature sensor, which means the system cannot safely monitor the heat of the water and has stopped working as a precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: NTC1 short circuit
What causes this fault?
This fault occurs when the boiler's main internal temperature sensor develops an electrical short, preventing it from reading how hot the water is. The most common reason is that the sensor itself has failed internally, or moisture has compromised the electrical connections between the sensor and the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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