Medium
7 03 on Ariston E-Combi One 30

Your boiler is having trouble communicating with one of its internal temperature sensors, which may cause your heating or hot water to work inconsistently.

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 outgoing 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 →7 04View →

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