Nordyne Light Commercial Air Handler B5SM -090 - Manual (Page 7)

7
ELECTRICAL WIRING
WARNING:
To avoid risk of electrical shock, personal
injury, or death, disconnect all electrical power
to the unit before performing any maintenance
or service. The unit may have more than one
electrical supply.
Label all wires prior to disconnection when
servicing the unit. Wiring errors can cause
improper and dangerous operation.
• Electrical connections must be in compliance with
all applicable local codes and ordinances, and with
the current revision of the National Electric Code
(ANSI/NFPA 70).
• For Canadian installations, the electrical connections
and grounding shall comply with the current Canadian
Electrical Code (CSA C22.1 and/or local codes).
Pre-Electrical Checklist:

Verify that the voltage, frequency, and phase of the
supply source match the specifi cations on the unit rating
plate. The label is located near the refrigerant lines.

Verify that the service provided by the utility is suffi cient
to handle the additional load imposed by this equipment.

Phase balance on 3 phase units must always be checked.
See Unbalanced 3-Phase Supply Voltage (page 8).
Line Voltage
• It is recommended that the line voltage to the unit be
supplied from a dedicated branch circuit containing the
correct fuse or circuit breaker for the unit.
• An electrical disconnect must be located within sight
of and readily accessible to the unit. This switch shall
be capable of electrically de-energizing the outdoor unit.
See unit data label for proper incoming fi eld wiring. Any
other wiring methods must be acceptable to authority
having jurisdiction.
• Refer to the unit wiring label for proper high and low
voltage wiring.
• Use only copper wire for the line voltage power supply
to this unit (Table 2, page 6). Use proper code agency
listed conduit and a conduit connector for connecting
the supply wires to the unit.
• Overcurrent protection must be provided at the branch
circuit distribution panel and sized as shown on the unit
rating label and according to applicable local codes.
See the unit rating plate for maximum circuit ampacity
and maximum overcurrent protection limits.
• If replacing any of the original wires supplied with the
unit, the replacement wire must be copper wire consisting
of the same gauge and temperature rating.
• Provide power supply for the unit in accordance with
the unit wiring diagram, and the unit rating plate. The
installer should become familiar with the wiring diagram/
schematic before making any electrical connections to
the unit. See Figure 6 (page 13).
• These air handlers can be purchased in both single
and three phase power confi gurations, all single phase
equipment is shipped from the factory ready for fi eld
connections. For electrical connection locations see
Figures 4 or 5 (pages 10 or 11).
• Three phase units are shipped from the factory pre-
confi gured for high voltage operation. The 460 volt, 60
hertz units may be reconfi gured in the fi eld for the other
voltages indicated on the unit rating label . For additional
Maximum Current Ampacity (MCA), or Maximum Over-
current Protection (MOP) information, refer to the unit
rating label. For proper high voltage wiring or other wiring
requirements refer to the Wiring Diagram (Figure 6).
• Internally mounted circuit breakers are available as fi eld
installed options. These circuit breakers can be used
as an electrical disconnect.
Thermostat Connections
• Thermostat connections shall be in accordance with the
instructions supplied with the thermostat and the indoor
equipment. The low voltage wires must be properly
connected to the units low voltage terminal block.
• A single stage thermostat is used with this equipment
and must operate in conjunction with any installed
accessories. A typical AC and air handler hookup is
shown in Figure 7 (page 14). For heat pump and air
handler connections, see Figure 8 (page 15).
• The thermostat should be mounted about 5 feet above
the fl oor on an inside wall. DO NOT install the thermostat
on an outside wall or any other location where its
operation may be adversely affected by radiant heat from
fi replaces, sunlight, or lighting fi xtures, and convective
heat from warm air registers or electrical appliances.
Refer to the thermostat manufacturer’s instruction sheet
for detailed mounting and installation information.
Electrical Wiring with a Duct Heater
Slip-in duct heaters are available as an accessory with
the B5SM air handler. See Table 3 for available sizes.
These heaters mount in the supply duct external to the
air handler. The heater kits are available in 10, 16, 26,
and 36 KW sizes and 240 or 460 voltages. All heater kits
are set up for three phase operation. To wire the heater
kits to the B5SM air handler unit, refer to the Installation
Instructions supplied witht he kit.
SKU Kw Volts/Phase/Hz MODEL
559428 10 208-240/3/60 H7HK010Q-01
559429 10 480/3/60 H7HK010S-01
559430 16 208-240/3/60 H7HK016Q-01
559431 16 480/3/60 H7HK016S-01
559432 26 208-240/3/60 H7HK026Q-01
559433 26 480/3/60 H7HK026S-01
559434 36 208-240/3/60 H7HK036Q-01
559435 36 480/3/60 H7HK036S-01
Table 3. Duct Mount Heater Kit Models