Low
05 on Ariston Euro Prisma 24

Your boiler is simply performing a routine automatic safety check to prevent its internal parts from freezing up 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-freeze - pump only: the circulating pump operates for one minute and the diverter valve switches every 23 hours. The pump starts at 8°C.

Engineer required

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

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