BoilerFaultCodesYour boiler has stopped working because the water pressure in the central heating system is too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low water pressure. Fill central heating system, pressure 0.7bar min.
What causes this fault?
This fault occurs when the water level inside your central heating system drops too low for the boiler to operate safely. It is usually caused by a small leak in the pipework or radiators, or because the air cushion inside the expansion vessel has depleted over time.
This issue often surfaces in autumn when the heating is turned on for the first time after summer, as the change in temperature can highlight existing pressure drops.
DIY fix possible
Locate the filling loop, which is usually a silver flexible hose with one or two small taps.Slowly open the tap(s) until you hear water entering the system.Watch the pressure gauge and close the taps firmly once it reaches between 1.0 and 1.5 bar.
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