BoilerFaultCodesMalvern 1.0 Fault Code
Also written as 10 — same fault.
The Malvern 1.0 fault code means: your boiler has detected that the water pressure inside the system is too low to operate safely.. It appears on 1 Malvern model in our database.
Technical description: Bar Vessel Pressure (Vessel Volume 8, 8, 8, 12, 18)
DIY fix possible
Locate the filling loop (usually a silver braided hose with one or two valves) underneath the boiler.Open the valve(s) slowly to allow mains water to enter the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valve(s) tightly and check for any signs of leaking.
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Malvern models that show the 1.0 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Malvern 1.0 fault code information on this page is sourced and cross-checked against the official Malvern service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026