Low
760 on Navien NCB 28 HE

Your boiler has reached its programmed service timer and is simply reminding you that it is time to have a professional technician perform a routine maintenance check to prevent limescale buildup.

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

Lime Alarm: Displays when the set time period has been reached to indicate a flush or service is necessary.

Engineer required

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

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