High
705 on Ariston Alteas One

Your boiler is having trouble communicating with the internal electronic controls, meaning it cannot process instructions to heat your home.

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 →703View →704View →

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