Low
dd.. on Ariston Genus 27

This is a normal operational message indicating that the boiler is currently heating water for your taps or shower.

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

Domestic hot water, burner on

DIY fix possible

No action is required as this is a status indicator rather than a faultTurn off the hot water tap to see the code disappearCheck that no taps are dripping if the code stays on when water is not in use

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