612 High

Ariston 612 Fault Code

The Ariston 612 fault code means: your boiler’s fan is not spinning at the correct speed, which means it cannot safely move air and gas through the system to provide heating or hot water.. It appears on 3 Ariston models 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: Fan error — speed higher or lower than set values
Typical repair cost £180-450 (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 612 fault code

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

Source

Ariston 612 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 7 July 2026