High
612 on Ariston Alteas One

Your boiler's fan is not spinning at the correct speed, which prevents the unit from starting up safely for heating or hot water.

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

Clas HE Evo CombiClas He Evo SystemE-Combi EvoE-system EvoClas net one combiClas one combiClas system one

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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