High
702 on Ariston Alteas One

Your boiler has detected a communication error between its internal control boards or with an external sensing component, causing it to stop working.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

E-Combi EvoE-System EVOClas HE evo CombiClas HE evo System

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

701View →703View →705View →

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