Pressure Gauge J < 0.5 bar High

Ariston Pressure Gauge J < 0.5 bar Fault Code

Also written as PRESSUREGAUGEJ05BAR — same fault.

The Ariston Pressure Gauge J < 0.5 bar fault code means: your boiler has stopped working because the water pressure is too low for the system to circulate heat safely.. It appears on 1 Ariston model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Shutdown Due To Insufficient Circulation. If the boiler is off, one possible cause for this state is an insufficient pressure of water in the system.
Typical repair cost £0-120 (including labour)

DIY fix possible

Locate the filling loop (usually a silver braided hose with small valves underneath the boiler).Slowly open both taps/levers on the filling loop to allow water into the system.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close both taps tightly.

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Ariston models that show the Pressure Gauge J < 0.5 bar fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ariston Pressure Gauge J < 0.5 bar fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026