Navien NHB-055 Installation & Operation Manual page 56

2. On the slave boiler, press and hold the Diagnostic and Down(-
) buttons for more than 2 seconds. "SL.01" will appear on the
display to confirm that this boiler is set as a slave.
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3. Repeat step 2 to configure the rest of the slave boilers in the
system.
4. On the master boiler, press and hold the Diagnostic and Up(+)
buttons for more than 5 seconds. All the display screens on the
configured boilers will return to the temperature display.
To add additional slaves at a later time, repeat step
Note
2.
To cancel the cascade communication setup, on the
master boiler, press and hold the Diagnostic and
Reset buttons for more than 5 seconds. The boilers
will revert to independent operation. Repeat steps
1-4 to reassign the master boiler.
56 Installing a Cascade System
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psi
psi