1 0 5 High

Ariston 1 0 5 Fault Code

Also written as 105 — same fault.

The Ariston 1 0 5 fault code means: your boiler is struggling to push water around your heating system, likely due to low pressure or a blockage.. 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: Insufficient circulation
Typical repair cost £100-250 (including labour)

DIY fix possible

Check your boiler pressure gauge and ensure it reads between 1.0 and 1.5 barIf the pressure is low, use the filling loop to top it up to the required levelEnsure all your radiator valves are fully open to allow water to circulate freely

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Ariston models that show the 1 0 5 fault code

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

Source

Ariston 1 0 5 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