How much does it cost to fix Ariston error code 3 0 2?

Typical repair cost for the Ariston 3 0 2 fault is £150-300 including labour.

3 0 2 High

Ariston 3 0 2 Fault Code

Q: What does the Ariston 3 0 2 fault code mean?

Your boiler's internal computer is struggling to talk to its main control unit, causing the system to stop working as a safety precaution.

Also written as 302 — same fault.

The Ariston 3 0 2 fault code means: your boiler's internal computer is struggling to talk to its main control unit, causing the system to stop working as a safety precaution.. It appears on 1 Ariston model in our database.

Technical description: GP-GIU communication error

Typical repair cost £150-300 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Ariston models that show the 3 0 2 fault code

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

HS Premium Repair: £150-300

Source

Ariston 3 0 2 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