BoilerFaultCodesYour boiler has stopped working because a sensor that monitors the temperature of the water leaving the unit has failed or has a loose connection.
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 read the temperature of the water being sent to your radiators. The most common reason is that the flow thermistor has physically degraded over time or developed an electrical short, though it can also be caused by a vibrating or loose wiring connection inside the unit.
This fault often appears when the heating is first turned on after summer, as the sudden change in temperature can push a struggling sensor to total failure.
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 F6 — no call-out fees, no surprises.
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