BoilerFaultCodesYour boiler has detected an issue with the sensor that measures water temperature as it leaves the unit, which is preventing it from heating correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow sensor fault – sensor needs changing
What causes this fault?
This fault occurs when the boiler's internal computer can no longer get an accurate reading from the thermometer attached to the main heat exchanger. The most common reason is that the sensor has physically failed or started sending 'out of range' signals, but it can also be triggered by loose or damaged electrical connections 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.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like A42 — no call-out fees, no surprises.
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Ferroli Modena HE is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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