Medium
7 04 on Ariston Genus HE

Your boiler is having trouble reading the temperature in one of your heating zones, which means it may not be heating that specific part of your home 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

Zone 3 return sensor defective

From this model's manual
Verified against the Ariston Genus He installation & service manual, page 34.
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

7 01View →7 02View →7 03View →

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