Connecting The Communication Cables - Navien NHB-055 Installation & Operation Manual

8.1.1 Piping Sizes and Considerations
When plumbing a cascade system, consider the following pipe
diameters and flow rates. Note that flow rates above 4 ft/s may
cause pipe erosion or velocity noise. These specifications may vary
depending on installation conditions.
NHB-110
Flow Rate (GPM)
Qty
@ 20°F ΔT
2 20.4
3 30.6
4 40.8
5 51
6 61.2
7 71.4
8 81.6
9 91.8
10 102
11 112.2
12 122.4
13 132.6
14 142.8
15 153
16 163.2
NHB-150
Flow Rate (GPM)
Qty
@ 20°F ΔT
2 27.6
3 41.4
4 55.2
5 69
6 82.8
7 96.6
8 110.4
9 124.2
10 138
11 151.8
12 165.6
13 179.4
14 193.2
15 207
16 220.8
Recommended
Boiler Pipe Sizes (2-4 ft/s)
1- 1/2"
2"
2"
2- 1/2"
2- 1/2"
3"
3"
3- 1/2"
3- 1/2"
3- 1/2"
3- 1/2"
4"
4"
4"
4"
Recommended
Boiler Pipe Sizes (2-4 ft/s)
2"
2"
2- 1/2"
3"
3"
3- 1/2"
3- 1/2"
3- 1/2"
4"
4"
4"
5"
5"
5"
5"

8.2 Connecting the Communication Cables

Up to 16 boilers can be connected with Navien Ready-Link
communication cables. Select one of the boilers in the cascade
system as the master boiler, and then connect the other boilers to
it as slaves. Before making any connections, ensure that the power
is turned off to all boilers.
Connect the Ready-Link cables to the J6 ports on the right side of
the front panel:
S R O/R
8.2.1 Configuring the Communication Settings
After connecting the Ready-Link communication cables, restore
power to the boiler and turn on all boilers using the Power button.
To configure the communication settings:
1. On the master boiler, press and hold the Diagnostic and Up(+)
buttons for more than 5 seconds. "MA.00" will appear on the
display to confirm that this boiler is set as the master.
S
R O/R
psi
S R O/R
psi
psi
Installing a Cascade System 55