BoilerFaultCodesYour boiler has detected an issue with the sensor that tracks the flow of hot water, which may cause your hot water to stay cold or run inconsistently.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Actual flow rate turbine (combi only)
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect water moving through the system even when you turn on a hot tap. It is usually caused by the internal turbine becoming stuck due to debris or limescale buildup, or a loose electrical connection between the sensor and the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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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