BoilerFaultCodesYour boiler has detected that the water pressure is incorrect or the sensor that monitors it is not communicating properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water transducer – check system water pressure
What causes this fault?
This fault occurs when the boiler's internal sensor detects that there is not enough water pressure to operate safely. The most common reason is a slow leak somewhere in your central heating system or air being released from the radiators, which causes the pressure to drop below the required threshold. It can also be caused by the sensor itself becoming blocked with debris or failing electronically.
This issue often appears in autumn when the heating is turned on for the first time after summer, as natural pressure loss over several months becomes apparent.
DIY fix possible
Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is too low, use the filling loop valves to top up the system until the gauge reaches 1.2 bar.Reset the boiler to see if the fault clears.
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