Medium
7 03 on Ariston Clas Net One

Your boiler is having trouble reading the temperature for the third heating zone in your home, which may cause that specific area to stop heating properly.

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 send 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 01View →7 02View →

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