BoilerFaultCodesYour boiler has lost its ability to measure the temperature of the water leaving the unit, usually due to a faulty sensor or a wiring issue.
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 flow NTC fault
What causes this fault?
This fault occurs when the boiler's internal computer can no longer detect a reliable signal from the sensor that monitors the temperature of the water being sent to your radiators. The most common reason is that the sensor itself has failed internally due to age, or the electrical connection between the sensor and the main control board has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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