BoilerFaultCodesYour boiler has lost water pressure and has shut down as a safety precaution to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Zero pressure. Requires ‘re-pressurising’
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe operating limit, causing the boiler to shut down to prevent internal overheating. Common reasons include a slow leak from a radiator valve or pipework, or a failure in the expansion vessel which allows the system pressure to escape through the safety discharge pipe.
This issue is frequently seen in autumn when the heating is turned back on for the first time, as the change in temperature can highlight small leaks or pressure losses developed over the summer.
DIY fix possible
Locate the filling loop (the flexible silver hose) underneath or near the boiler.Slowly open the one or two valves on the loop while watching the pressure gauge.Close the valves tightly once the gauge needle reaches between 1 and 1.5 bar.
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