BoilerFaultCodesYour boiler has detected that the water pressure in the central heating system is too low to operate safely and has shut down.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Insufficient system water pressure appliance operation
What causes this fault?
This fault occurs when the internal sensor detects that there isn't enough water pressure to safely circulate heat around your home. The most common reason is a slow leak somewhere in the radiator network or a drop in pressure following the bleeding of your radiators. In some cases, a component inside the boiler like the expansion vessel may have lost its charge, leaving the system unable to maintain steady levels.
This code is frequently seen at the start of autumn when homeowners turn their heating back on for the first time after summer, or after bleeding radiators for the winter months.
DIY fix possible
Locate the external filling loop, which is usually a flexible silver hose with one or two black taps underneath the boiler.Slowly open both taps (or one if there is only one) until you hear water flowing into the boiler.Watch the pressure gauge on the front of the boiler and close the taps once the needle reaches between 1.0 and 1.5 bar.Press the Reset button on the boiler control panel to clear the fault code.
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