How much does it cost to fix Ariston error code INSUFFICIENT WATER?

Typical repair cost for the Ariston INSUFFICIENT WATER fault is £80-150 including labour.

INSUFFICIENT WATER High

Ariston INSUFFICIENT WATER Fault Code

Q: What does the Ariston INSUFFICIENT WATER fault code mean?

Your boiler has detected that the water pressure inside the system is too low to run safely and needs to be topped up.

Also written as INSUFFICIENTWATER — same fault.

The Ariston INSUFFICIENT WATER fault code means: your boiler has detected that the water pressure inside the system is too low to run safely and needs to be topped up.. It appears on 7 Ariston models in our database.

Technical description: Insufficient water indicator light come on (within 40 sec.)

Typical repair cost £80-150 (including labour)

DIY fix possible

Locate the external filling loop, which is usually a flexible pipe with one or two valves underneath the boiler.Slowly open the valve(s) 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.Ensure both valves are fully closed and check the boiler display to see if the error light has cleared.

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Ariston models that show the INSUFFICIENT WATER fault code

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

Source

Ariston INSUFFICIENT WATER 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