Medium
8 04 on Ariston Genus ONE Net

Your boiler is signalling that an additional electronic control module, required for managing specific heating zones or complex setups, has not been detected or is not communicating correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Decoupling Clip-In required (see note)

From this model's manual
Verified against the Ariston Genus One Net installation & service manual, page 37.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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Related fault codes

8 01View →8 02View →8 03View →

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