BoilerFaultCodesYour boiler has detected that the water pressure is too low or a safety switch has disconnected, causing the system to shut down for protection.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Water Switch System pressure too low | Water Switch - plug disconnected Waterswitch activated
What causes this fault?
This fault occurs when the boiler's internal safety sensor detects that there isn't enough water pressure flowing through the heat exchanger to operate safely. The most common reason is a gradual leak in the central heating system or air trapped in the pipes, but it can also be caused by a loose wire or a faulty pressure switch failing to send a signal to the main control board.
This fault often appears after the summer break when the heating is first turned back on, as static water pressure can drop during long periods of inactivity.
DIY fix possible
Check the pressure gauge on the front of the boilerIf the needle is below 1.0 bar, locate the filling loop (braided silver hose) underneath or near the boilerSlowly open the tap(s) on the filling loop to add water until the pressure reaches 1.5 barClose the taps tightly and press the 'Reset' button (flame symbol with a cross over it)
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