BoilerFaultCodesYour boiler has lost its connection to the sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow–NTC: – NTC broken – NTC cable broken – Defective connection at NTC – Defective connection at electronics | Flow–NTC cable defective/broken NTC faulty
What causes this fault?
This fault occurs when the boiler's main control board loses the electrical signal from the sensor that monitors hot water leaving the unit. The most common reason is that the sensor itself has internal electrical failure or the wiring connecting it to the circuit board has become loose or damaged over time.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F.0 — no call-out fees, no surprises.
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