High
7 05 on Ariston Clas HE Evo

Your boiler is struggling to accurately measure the water flow between your heating system and your hot water tank, which is stopping it from working properly.

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

Hydraulic separation sensor defective

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

7 04View →7 06View →

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