Low
05 on Ariston Egis 24 MFFI

Your boiler has detected very cold temperatures and is running the pump automatically to prevent the internal pipes from freezing.

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

Pump anti-freeze: When the boiler senses a temperature of 8°C or lower, the pump will run for 2 minutes, the boiler will then check if the flow temperature is higher than 8°C.

From this model's manual
Verified against the Ariston Bravo 24 Mffi installation & service manual, page 7.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Ensure the boiler remains plugged in and the mains power switch is kept onCheck that your external condensate pipe is not frozen if temperatures are below zeroIncrease the room thermostat slightly to help warm the system pipes naturally

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