BoilerFaultCodesYour boiler has stopped working because a sensor that monitors the temperature of the water in your heating system has become loose or disconnected from its pipe.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Central heating NTC not connected to pipe
What causes this fault?
This fault occurs when the main temperature sensor responsible for monitoring the central heating water loses physical contact with the copper pipe it is designed to sit on. The most common reason is that the metal clip holding the sensor has weakened over time or been knocked loose, preventing the boiler from accurately measuring the water temperature. In some cases, the internal wiring has frayed or become disconnected, breaking the signal between the sensor and the main control board.
This fault often appears at the start of autumn when the heating system is first turned back on after summer, as the sudden vibration and thermal expansion in the pipes can cause a loose sensor to finally shift out of position.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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