BoilerFaultCodesYour boiler has stopped working because it can no longer accurately measure the temperature of the water leaving the unit.
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 control board loses communication with the sensor that monitors the outgoing water temperature. The most common reason is that the sensor's internal electrical circuit has broken or its wiring has come loose, meaning the boiler can no longer operate safely without knowing how hot the water is.
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.00 — no call-out fees, no surprises.
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