BoilerFaultCodesYour boiler has lost its connection to the sensor that measures the water temperature as it leaves the unit, meaning it cannot safely judge how much heat to provide.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Interruption feed temperature sensor (NTC): NTC faulty, NTC cable faulty, faulty plug connection on NTC, faulty plug connection on the electronics
What causes this fault?
This fault occurs when the boiler's central brain loses communication with the temperature sensor on the main pipe. The most common reason is a physical breakage in the internal wiring or the sensor itself failing due to age and constant heat cycles. Without this signal, the boiler shuts down as a safety precaution because it cannot monitor if the water is becoming dangerously hot.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.0 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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