Table of Contents
Advertisement
34
N
G
H
120 VAC
LINE
CR1
9
ALARM
8
7
CR1
120V
F3
GND
NEUT
2
5
***
DHW
4
PUMP
6
***
BOILER
1
PUMP
3
10
**** DHW TANK
11
12
OUTDOOR
13
14
TT TERMINALS
15
+
16
0-10 VOLT
-
17
J3-3
RS485 BUS
J3-4
J3-5
J4-3
J4-4
RS485 BUS
J4-4
X4-5
X4-6
X4-15
X4-16
BLOWER
MOTOR
GAS VALVE
X5-3
RELAY
X5-4
X4-8
X4-9
DETAIL "A"
*
LOW WATER LEVEL APPLICATION FOR STANDARD BOILER ONLY ( NOT FOR VWH )
FLOW SWITCH FOR VWH APPLICATION ( OPTIONAL FOR STANDARD BOILER APPLICATION )
**
MAX 3 AMPS/120 VAC. USE CONTACTOR IN PLACE OF PUMP FOR GREATER DRAW.
***
FOR DOUBLE STACK UNITS - SUPPLY MANIFOLD SYSTEM SENSOR BOTTOM BOILER
****
Figure 25 - Internal Connection Diagram
observe boiler function to verify the installation is working properly.
NOTE: Installing the optional flow switch will disable the built-in low
water cutoff. If a flow switch and a low water cutoff are necessary
for the installation, purchase and install the optional UL353 LWCO
(available from Westinghouse, Part # 7350P-601). In this installation,
it is recommended to install the flow switch kit first.
N. Optional UL353 Low Water Cut-Off Interface Kit
NOTE: This boiler will require 2 interface kits to ensure both heat
exchangers are full of water.
1. If an optional UL353 low water cut-off (LWCO) interface kit is used,
the control box of the kit should be mounted to the left side of the
boiler cabinet near the low water cut-off probe, which is located on
the outlet nipple of the boiler.
2. If the optional flow switch is present on the boiler, then the orange
wire from the LWCO control box is left unconnected. If the optional
flow switch is not installed on or connected to the boiler, remove
the wire connected to the low water cut-off probe on the boiler and
whl-428-r1 Rev. 001 Rel. 012 Date 7.21.20
J7-1
J7-3
J6-1
J8-3
J6-3
CONDENSATE
RECEPTICAL
J8-4
J8-1
J6-2
CR1
J6-4
F2
J6-5
F1
J6-6
J5-1
J5-2
J5-3
J5-4
J5-5
B
A
J5-10
J5-9
J5-8
J5-7
J5-6
JUMPER IN 'B' POSITION
FOR ALL MODCON UNITS
120V
WIRING CONNECTION DIAGRAM
POWER
SWITCH
X5-7
X5-5
CONTROL
X5-8
X4-2
X4-14
X4-10
X8-8
X4-3
X8-3
X8-6
X4-1
X4-11
X4-13
SUPPLY
X8-1
X4-12
RETURN
X8-2
AUTO RESET
MAN RESET
HIGH WATER
HIGH WATER
TEMP
TEMP
X4-7
X4-17
connect it to the orange wire from the newly mounted LWCO control
box.
3. Connect the single red wire from the control box to the low water
cut-off probe on the boiler.
4. Route the rest of the wires through the hole provided in the cabinet
and down by the main electrical enclosure.
5. Locate the two pigtails hanging from the main electrical enclosure.
Select the pigtail which has a white, red, and brown wire in it. If the
pigtail is connected to a gas pressure switch, skip to step 7. If this
pigtail is not connected to a gas pressure switch, 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
1000 and 1700
X6-2
X6-4
X6-1
ORANGE SPARK CABLE
TO SPARK ELECTRODE
FLAME RECTIFICATION
X6-5
X4-5
X4-6
926
X4-15
X4-16
X5-3
X5-4
SEE DETAIL "A" FOR 120V GAS
VALVE WIRING APPLICATION
X4-8
X4-9
24VAC <12VA
GAS VALVE
CONDENSATE
FULL
X8-4
X8-10
FLAPPER
VALVE
X8-9
X4-19
X4-20
LOW WATER
LEVEL
FLUE
BVPS
ECO
X4-18
X4-4
X8-5
HIGH GAS
PRESSURE
X-2
X8-7
RIBBON CABLE
TEXT DISPLAY
PROBE
BLOWER
MOTOR
*
*
*
FLOW SWITCH
REAR
FRONT
THERMAL
TEMP LIMIT
FUSE
SWITCH
UL353
LOW GAS
LWCO
PRESSURE
OPTIONAL
Advertisement
Table of Contents
