BoilerFaultCodesYour boiler has lost its connection to the sensor that monitors the temperature of the water leaving the unit, causing it to stop running as a safety precaution.
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 open circuit
What causes this fault?
This fault occurs when the boiler's internal computer can no longer detect a signal from the sensor that monitors hot water leaving the unit. The most common reason is that the sensor itself has failed internally or the electrical wiring connecting it to the main control board has become loose or damaged. Because the boiler cannot safely verify how hot the water is, it shuts down to prevent overheating.
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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