Medium
7 04 on Ariston Clas System 28

Your boiler is struggling to accurately read the temperature of the water returning from one of your heating zones, which may cause your heating system to operate inefficiently or stop working in that specific area.

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

Zone3 Return Probe Damaged

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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