Low
TEC on Navien NCB CE

Your boiler has reached its internal timer for a routine service and is simply reminding you that it is time for a professional maintenance check.

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

Maintenance alarm. Generated when the power-on duration in days is greater than the value set at “W.Maintenance time”.

Engineer required

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

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