Medium
7 01 on Ariston Clas Net One

Your boiler is struggling to accurately measure the temperature of the water being sent to your radiators, which means the heating system may not work as expected.

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 1 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 02View →7 03View →

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