BoilerFaultCodesYour boiler has detected that the water pressure is too low for it to operate 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: If the boiler loses water: the pressure will be indicated, see diagram 1 (a) and the boiler ON indicator (b) will flash red indicating a fault.
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to pump heat around your home. The most common reason is a slow leak somewhere in the central heating system or air being released from the radiators, which leaves the boiler with too little water to operate safely.
This issue often appears in autumn when the heating is turned back on for the first time, as the change in temperature can highlight small leaks or pressure drops that occurred while the system was dormant.
DIY fix possible
Locate the filling loop (usually a silver flexible hose) under the boiler.Open the small valve taps slowly until you hear water flowing.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the valves completely.
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