How much does it cost to fix Ariston error code Insufficient water pressure?

Typical repair cost for the Ariston Insufficient water pressure fault is £80-120 including labour.

Insufficient water pressure High

Ariston Insufficient water pressure Fault Code

Q: What does the Ariston Insufficient water pressure fault code mean?

Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.

Also written as INSUFFICIENTWATERPRESSURE — same fault.

The Ariston Insufficient water pressure fault code means: your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.. It appears on 5 Ariston models in our database.

Technical description: INSUFFICIENT SYSTEM PRESSURE: In the event of insufficient water pressure in the heating system (less than 0.4 bar), a safety device will shutdown the boiler.

Typical repair cost £80-120 (including labour)

DIY fix possible

Locate the filling loop (a silver flexi-hose) beneath the boiler.Open the small black or blue tap(s) to let water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the tap(s) firmly once the correct pressure is reached.

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Ariston models that show the Insufficient water pressure fault code

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

Source

Ariston Insufficient water pressure 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