Electrical Connections; Line Voltage Connections; External Connections - UTICA BOILERS UBSSC-299 Installation, Operation & Maintenance Manual

8.1 General
Electrically bond boiler to ground in accordance with
requirements of authority having jurisdiction. Refer to:
• USA- National Electrical Code, ANSI/NFPA 70.
8.2 Electric Knockouts (figure 8-1)
• Five knockouts located on bottom of chassis.
A. Three knockouts located under junction box are
reserved for high voltage wires. Choose connectors
using total diameter of wire bundles.
B. Two knockouts located to right of high voltage
knockouts (outside of junction box) are reserved
for low voltage wiring. Use supplied grommets
when using these knockouts.
8.3 Line Voltage Connections (figure 8-2)
• Boiler
A. Provide individual 120V, 15 amp circuit
(recommended) with fused disconnect or service
switch as required by authority having jurisdiction.
B. Open High Voltage Junction Box (see figures 3-4
and 3-5) to access line voltage terminal strip.
C. Connect 120 VAC circuit to line voltage terminal
strip 120 VAC L,N,G.
• Central Heating Pump, if used.
A. Isolate pump from control module if pump FLA (Full
Load Amps) exceeds maximum allowable current
draw. See Figure 8-3
B. Connect pump to line voltage terminal strip CH
PUMP L,N,G.
• Domestic Hot Water Pump, if used.
A. Isolate pump from control module if pump FLA
exceeds maximum allowable current draw.
Figure 8-3 and Table 11.
B. Connect pump to line voltage terminal strip DHW
PUMP L,N,G.
8.4 External Connections (figure 8-4)
• User Interface Terminals
A. Factory wired to USER INTERFACE terminals
B. Optional - Remote mount user interface for
improved access. Use low voltage knockout.
C. Maximum wire length is 100 ft (30m) for 22 ga.
wire, or 150 ft (45m) for 18 ga. wire.
• Argus Link (Multiple boiler applications only)

8 - ELECTRICAL CONNECTIONS

.
and Table 11
See
!
WARNING
Electrical shock hazard. Turn OFF electrical power
supply at service panel before making electrical
connections. Failure to do so could result in death
or serious injury.
Wiring diagrams can be found in Section 14 of
Note
this Manual.
8-1
FIGURE Electric Knockouts Bottom Of Boiler
High Voltage
Knockouts
5"
4½"
(127mm)
(114mm)
8-2
FIGURE

Line Voltage Connections

Table 11 -
Maximum Allowable Current Draw
MBH CH PUMP
50
75 1 A
100
150
200 10 A
299
If CH or DHW pump current is more than the maximum
allowable current draw install proper field sourced relays
as shown in figure 8-3.
36
Front of Boiler
Low Voltage Knockouts
(Use supplied
grommets when using
these knockouts)
Back of Boiler
DHW PUMP NOTE
Powered by
1 A
Control Board
Powered by
10 A installed 10 Amp
relay
PN 240011320 Rev. G 10/01/2021]