BoilerFaultCodesGlow-worm low water pressure Fault Code
Also written as LOWWATERPRESSURE — same fault.
The Glow-worm low water pressure fault code means: your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.. It appears on 1 Glow-worm model in our database.
Technical description: The mains reset on/off switch is used to restart the boiler after a fault condition has occurred
DIY fix possible
Locate the filling loop, which is usually a silver braided hose with one or two small valves under the boiler.Open the valves slowly to allow mains water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valves tightly and press the reset button on the boiler to restart the system.
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Glow-worm models that show the low water pressure fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Glow-worm low water pressure fault code information on this page is sourced and cross-checked against the official Glow-worm service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026