Low
05 on Ariston Euro Combi 30 MFFI

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.

What the manual says

Manufacturer manual

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.

From this model's manual
Verified against the Ariston Euro Combi 30 Mffi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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