B07 Medium

Ariston B07 Fault Code

The Ariston B07 fault code means: your boiler is having trouble switching between heating your radiators and providing hot water because an internal switch has failed to trigger.. It appears on 3 Ariston models in our database.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description: Microswitch for Diverter Valve
Typical repair cost £120-£210 (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 B07 fault code

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

Source

Ariston B07 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