BoilerFaultCodesYour boiler has detected that the water pressure has dropped too low or there is a problem with the internal sensor that monitors it, causing the system to shut down for safety.
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 | Cause: Water Switch - plug disconnected, Waterswitch activated
What causes this fault?
This fault occurs when the boiler's internal safety mechanism detects that there isn't enough water pressure to operate safely. The most common reason is a physical leak in the system or air trapped in the radiators, but it can also be caused by a build-up of debris clogging the sensor or a loose electrical connection to the pressure switch.
This issue often appears when the heating is first turned on in autumn, as small leaks or air pockets may have developed during the months the system was dormant.
DIY fix possible
Check the central heating pressure gauge; it should ideally be between 1.0 and 1.5 bar.If the pressure is below 1.0 bar, use the external filling loop to top up the system until the gauge reaches the correct level.Restart the boiler to see if the fault clears.
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