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Heating  Heating

Brand

Navien Navien List all brands

Type:

NCB-180 view NCB-180 List all types

Error code:

E740
List all errors


Error code: E740

Cause of error code E740

Abnormal operation: outdoor temperature sensor (appears only when the outdoor reset curve is enabled).

Solution for error code E740

Ensure that the outdoor reset curve is configured properly.
Check the outdoor temperature sensor wiring connection.


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