High
60-70-80 (ll-ll-ll) on Ariston Clas HE 35

Your boiler has detected that the water is not flowing properly around your heating system, which is preventing it from heating up your home or 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

Lack of water circulation

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

101View →103View →

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