Low
E598 on Navien NCB500 NCB500-1S+/30K

Your boiler's internal clock has lost its settings, which usually means the system cannot keep time to manage your heating schedule correctly.

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

Abnormal operation: Panel real time clock

From this model's manual
Verified against the Navien/Navien Ncb500 Combi Service Manual30k En 250331 Pdf 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.

DIY fix possible

Locate the user menu on your boiler's control panel.Navigate to the date and time settings.Manually reset the current date and time to clear the error.

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All 60 fault codes on the NCB500 NCB500-1S+/30K

Seeing a different code? Every code this model can display, in one place.

001003004012016030031046047109205218302352353407421515517593594615740782E001E003E004E012E016E030E031E046E047E109E110E205E218E291E302E351E352E353E407E421E434E439E441E445E480E515E517E593E594E615E740E782E783E787E788

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