Medium
7 04 on Ariston Clas HE Evo

Your boiler is having trouble communicating with the temperature controls for the third heating zone in your property, which may cause that specific area to not heat up correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Zone 3 return sensor defective

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 02View →7 03View →

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