BoilerFaultCodesYour boiler has lost water pressure and has shut itself down to prevent damage, which is why your heating and hot water are currently unavailable.
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 system drops below the minimum level required for the boiler to operate safely. The most common reasons for this are a slow leak from a radiator valve or pipework, or the air pressure inside the internal expansion vessel needs topping up. When the pressure hits zero, the boiler detects the lack of water and shuts down to prevent the heat exchanger from overheating.
This issue is frequently seen in autumn when the heating is turned on for the first time in months, as the increased heat and pressure can expose small leaks that developed over the summer.
DIY fix possible
Locate the filling loop (a flexible silver braided hose) underneath the boiler.Open the one or two taps/valves on the filling loop slowly until you hear water flowing.Watch the pressure gauge on the front of the boiler until it reaches between 1.0 and 1.5 bar.Close the taps/valves tightly and the boiler should automatically reset.
Find a Gas Safe engineer
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