BoilerFaultCodesSaunier Duval Water pressure Fault Code
Also written as WATERPRESSURE — same fault.
The Saunier Duval Water pressure fault code means: your boiler has detected that the amount of water circulating through your heating system is too low, so it has safely stopped working to prevent any damage.. It appears on 2 Saunier Duval models in our database.
Technical description: Flashing pressure warning; check water pressure.
DIY fix possible
Locate the filling loop, which is usually a small silver braided hose with one or two valves located underneath the boiler.Slowly open the valve(s) to let 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 valve(s) tightly to stop the flow; the boiler should then automatically restart.
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Gas Safe Register →Saunier Duval models that show the Water pressure fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Saunier Duval Water pressure fault code information on this page is sourced and cross-checked against the official Saunier Duval service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026