BoilerFaultCodesYour boiler has stopped working because the water pressure inside the system has dropped below the minimum level required to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System pressure too low
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water circulating in your heating system to operate safely. The most common reason is a slow leak from a radiator valve or pipework, but it can also happen if you have recently bled your radiators and haven't topped the pressure back up.
This issue is more common in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
DIY fix possible
Locate the internal or external filling link (often blue levers or a braided hose under the boiler).Slowly open the valves until you hear water entering the system.Watch the digital display or pressure gauge until it reaches between 1.0 and 1.5 bar, then close the valves completely.
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