BoilerFaultCodesYour boiler has detected an issue with its internal sensor that monitors water pressure, preventing it from heating up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water pressure sensor fault.
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors internal water pressure. The most common reason is that the sensor has developed an electrical failure or has become blocked with system debris, preventing it from sending a steady signal. In some cases, the issue is caused by loose or damaged wiring connecting the sensor to the main computer.
DIY fix possible
Check the pressure gauge on the front of the boiler is between 1.0 and 1.5 barIf the pressure is low, use the filling loop underneath to top the system upReset the boiler using the power or reset button to clear the fault
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A boiler cover plan would cover faults like F9 — no call-out fees, no surprises.
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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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