Unknown
E788 on Navien NCB500

Navien NCB500 fault code E788

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Error code that appears if you try to change the gas type on the front panel

From this model's manual
Verified against the Navien/Navien Ncb500 System Service Manual 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.

Engineer required

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

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All 52 fault codes on the NCB500

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

001003004012016030031046047109205218302352353515517593594615740782E001E003E004E012E016E030E031E046E047E109E110E205E218E291E302E351E352E353E480E515E517E593E594E598E615E740E782E783E787

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