High
707 on Ariston Alteas One

Your boiler has detected an internal communication failure between the electronic control boards, meaning the main system cannot talk to its secondary controls.

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 →702View →705View →706View →

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