BoilerFaultCodesYour boiler has detected that the water pressure is too low for it to run safely and has shut down as a precaution.
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 Switch Not Operated
What causes this fault?
This fault occurs when the internal sensor detects that there is not enough water inside the central heating system to operate safely. The most common reason is a gradual loss of pressure through a small leak on a radiator valve or because the system was recently bled without being topped up.
This fault is more frequent in autumn when homeowners turn their heating back on for the first time, as the change in temperature and manual bleeding of radiators often causes the pressure to drop.
DIY fix possible
Locate the external filling loop, which is usually a silver flexible hose underneath the boiler.Open the small black valves at either end of the hose to allow water into the system.Monitor the pressure gauge on the front of the boiler until it reaches between 1 and 1.5 bar.Close both valves tightly and press the 'Reset' button on the boiler control panel.
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