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34
remove the jumper plug from the end of the pigtail and place
the jumper plug into the mating connector coming from the
LWCO control box.
6. Connect the pigtail to the remaining plug coming from the
LWCO control box. Installation is complete.
7. If the pigtail located in step 5 is connected to a gas pressure
switch, disconnect it from the gas pressure switch and connect
the pigtail to the mating connector coming from the LWCO
control box. Connect the gas pressure switch to the remaining
connector from the LWCO control box.
O. Wiring of Cascade System Communication Bus
1. A Cascade Bus Termination Plug has been installed on the
customer connection board of this boiler. The purpose of this
plug is to stabilize communication between multiple boilers and
reduce electrical "noise". See Figures 25 and 26 for Cascade Bus
Termination Plug installation detail.
NOTE: It is important that the termination plug in multiple
boilers (cascaded units) be installed as depicted in Figure 25.
Leave the plug installed in the J3 port on the Master boiler.
Remove the plug on intermediate Follower boilers. Move the
plug to the J4 port on the final Follower boiler.
2. Use standard CAT3 or CAT5 computer network patch cables
to connect the communication bus between each of the boilers.
These cables are readily available at any office supply, computer,
electronic, department or discount home supply store in varying
lengths. If you possess the skills you can also construct custom
length cables.
Figure 24 - Wiring Cascade System
Figure 25 - Cascade Termination Plug Detail
WHL-033 Rev. 1.29.16
3. It is recommended to use the shortest length cable that will
reach between the boilers and create a neat installation. Do
not run unprotected cables across the floor where they may
become wet or damaged. Avoid running communication
cables parallel and close to or against high voltage (120 volt
or greater) wiring. Westinghouse recommends that the
maximum length of communication bus cables not exceed
200 feet.
4. Route the communication cables through one of the
knockouts in the cabinet.
5. Connect the boilers in a daisy chain configuration as shown
below. It is best to wire the boilers using the shortest wire
runs rather than trying to wire them in the order that they
are addressed. The communication bus jacks on the customer
connection panel are interchangeable so you can use either
one or both in any order to connect the cable.
If you have connected the boilers to each other properly, there
will be no open communication connection ports.
P. Cascade Master Pump and Sensor Wiring
1. Place the cascade master overlay sticker onto the field
connection board on the boiler designated as the cascade
master.
2. Connect the system pump hot wire to the terminal marked
SYS PUMP.
3. Connect the system pump neutral to the BOILER NEUT
terminal and the pump ground wire to the BOILER GND
terminal.
of any voltage should be fed into
either of these terminals.
NOTE: Place the Cascade Master
label
envelope) on top of the boiler
designated Master.
4. Connect a jumper wire from
the 120 VOLT terminal to the
SYS PUMP PWR terminal.
5. Connect the boiler pump to
the terminals marked BOILER
HOT, BOILER NEUT, and
BOILER GND.
6. Connect the system pipe
sensor
to
the
terminals
marked SYS SENSOR.
7. Connect the outdoor sensor
(if used) to the terminals
marked OUTDOOR SEN.
8. Connect the signal to start
the system to the terminals
marked THERMOSTAT.
NOTE: This signal can come
from a room thermostat or a
dry contact closure. No power
(included
in
shipping
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