Navien NHB-055, Service Manual

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40 NHB Service Manual Version 1.0
4.4.9 Error occurrence history display
1. At the <Normal operation mode> or <Error display mode>,
press the [Info] button for over 2 seconds to access the error
history mode.
The most recent error will be displayed first.
2. When the [+] / [-] button is pressed, the error history can be
searched. A total of 10 errors are stored in memory and are
labelled from 0 to 9 with 0 being the most recent error.
3. Whenever the [Mode] button is pressed, the previous error
occurrence time difference (unit time, maximum 9999 hr.) and
the sub error code are toggled and displayed.
4. Pressing the [Reset] button for 5 seconds while in the
<ERROR HISTORY DISPLAY MODE> displays “CLR” and deletes
all the ERROR HISTORY DATA.
5. Press the [Reset] button once to return to the <Normal
operation mode>.
6. If there is no button input for 5 minutes, then the system
automatically returns to the <Normal operation mode>.
NOTE
●
While in <ERROR HISTORY DISPLAY MODE> the first digit
indicates the history of the error with 0 being the most
recent. The remaining 3 digits indicate the error code. If
there is no error history, a “0” will be displayed.
●
Passed time display: The time between the currently
displayed error and the just previously generated error is
displayed in 1-hr unit.
●
(“0” is displayed if the error code is empty)
●
Ex) When the most recent error code is 615, the sub error
code is 5, and 24 hours have passed since the error was
generated.
●
When the Sub Error Code is “0” (i.e., there is no sub error
code), the display is as follows: