Low
60-80 (ll-ll) on Ariston Clas HE 28

Your boiler is perfectly safe and is simply running its internal pump to prevent its pipes from freezing during cold weather.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Anti-frost mode on (pump in operation)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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