BoilerFaultCodesVokera Pressure below 0.5 bar Fault Code
Also written as PRESSUREBELOW05BAR — same fault.
The Vokera Pressure below 0.5 bar fault code means: your boiler has stopped working because the water pressure is too low to operate safely.. It appears on 3 Vokera models in our database.
Technical description: The minimum permissible level for the safe and efficient operation of the appliance is 0.5 bar. Should the pressure fall below 0.5 bar, the boiler shuts off automatically.
What causes the Vokera Pressure below 0.5 bar fault?
This fault occurs when there isn't enough water circulating within your central heating system to allow the boiler to fire up safely. The most common cause is a slow leak from a radiator valve or pipework, though it can also happen if you have recently bled your radiators and didn't top up the water levels afterwards.
This issue is more frequent in autumn when homeowners turn their heating back on for the first time, as the change in system pressure can expose small leaks that developed over the summer.
DIY fix possible
Locate the filling loop (a flexible silver hose) underneath or near the boiler.Slowly open the one or two taps/valves on the hose until you hear water entering.Close the taps once the pressure gauge on the front of the boiler reaches between 1.0 and 1.5 bar.
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Gas Safe Register →Vokera models that show the Pressure below 0.5 bar fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera Pressure below 0.5 bar fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026