Low
7 03 on Ariston Clas HE 24

Your boiler has lost signal from a temperature sensor responsible for a specific heating zone, which may prevent that part of your home from heating up correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

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 →

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