Aerco Benchmark 3.0LN Series, Installation, Operation & Maintenance Instructions Manual

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INSTALLATION
2-6
The IRI gas train is an optional gas train
configuration which is required in some areas for
code compliance or for insurance purposes.
The IRI gas train is factory pre-piped and wired.
See Appendix F, Drawing AP-A-803 for details.
2.8 AC ELECTRICAL POWER WIRING
The AERCO Benchmark 3.0 Electrical Power
Wiring Guide, GF-3060, must be consulted prior
to connecting any AC power wiring to the unit.
External AC power connections are made to the
unit inside the Power Box on the front panel of
the unit. Remove the front door of the unit to
access the Power Box mounted directly above
the Control Box. Loosen the four Power Box
cover screws and remove cover to access the
AC terminal connections inside the Power Box
(Figure 2-8).
NOTE
All electrical conduit and hardware must
be installed so that it does not interfere
with the removal of any unit covers, inhibit
service/maintenance, or prevent access
between the unit and walls or another
unit.
TERMINAL BLOCK
configuration ordered. The two different terminal
block configurations are shown in Figure 2-9. A
wiring diagram showing the required AC power
connections is provided on the front cover of the
Power Box.
Each Benchmark 3.0 Boiler must be connected to
a dedicated electrical circuit. NO OTHER
DEVICES
SHOULD BE ON THE SAME
ELECTRICAL CIRCUIT AS THE BENCHMARK
BOILER.
A double-pole switch must be installed on the
electrical supply line in an easily accessible
location to quickly and safely disconnect electrical
service. DO NOT attach the switch to sheet metal
enclosures of the unit.
After placing the boiler in service, the ignition
safety shutoff device must be tested. If an external
electrical power source is used, the installed boiler
must be electrically bonded to ground
in
accordance with the requirements of the authority
having jurisdiction. In the absence of such
requirements, the installation shall conform to
National Electrical Code (NEC), ANSI/NFPA 70
and/or the Canadian Electrical Code (CEC) Part I,
CSA C22.1 Electrical Code.
For electrical power wiring diagrams, see the
AERCO Benchmark 3.0 Electrical Power W iring
Guide, (GF-3060).
208 VAC, 3 PHASE 460 VAC, 3 PHASE
GND
NEU
GND
L3 L3
L2 L2
L1 L1
UPPER RIGHT CORNER OF FRONT PANEL
Figure 2-8
208 VAC, 3 Phase
460 VAC, 3 Phase
AC Input Terminal Block Location
2.8.1 Electrical Power Requirements
The AERCO Benchmark 3.0 Boiler is available
in two different AC power configurations:
•
208 VAC/3-Phase/60 @20 amps
• 460 VAC/3-Phase/60 Hz @ 15 amps
Each of the power configurations utilize a Power
Box with a terminal block that matches the
Figure 2-9
AC Terminal Block Configurations
2.9 MODES OF OPERATION AND FIELD
CONTROL WIRING
The Benchmark 3.0 Boiler is available in several
different modes of operation. W hile each unit is
factory configured and wired for its intended
mode, some additional field wiring may be
required to complete the installation. This wiring
is typically connected to the Input/Output (I/O)
Box located on the lower portion of the unit front