Medium
7 03 on Ariston Clas One

Your boiler is having trouble communicating with one of the heating zones in your home, which means that specific area may not be receiving heat 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 3 flow sensor open / short circuit

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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