10
• Use only copper wire for the line voltage power supply
to this unit. Use proper code agency listed conduit and
a conduit connector for connecting the supply wires to
the unit. Aluminum supply wire may be used if a heater
kit is installed.
• Provide power supply for the unit in accordance with the
unit wiring diagram, and the unit rating plate. Use UL
listed conduit and conduit connectors for connecting the
supply wires to the unit and for proper grounding. Field
supplied bushings for the power supply cables must be
added to support and protect the power supply cables.
• 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.
• Circuit breakers installed in the B5BV series electric
furnace are for short-circuit protection of the internal
wiring and to serve as a unit disconnect. They do not
provide over-current protection of the supply wiring.
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 and Table 4 (page 15) for maximum
circuit ampacity and maximum overcurrent protection
limits.
• All 208/230 Volt units are shipped from the factory wired
for 240 volt operation. For 208V operation, remove the
lead from the transformer terminal marked 240V and
connect it to the terminal marked 208V.
Single Circuit Adaptor Kit
If a single circuit adaptor kit is used, it may need to be re-
configured for some applications. Remove the single circuit
adaptor kit cover and verify that the lugs are configured
correctly for the application. If the lugs are not configured
for the application, refer to the instructions included with
the kit and modify the configuration.
Install the single circuit adaptor kit (if used) in the line
side (“on” end) of the circuit breakers. Tighten the lugs
securely (45 in-lbs recommended).
Connect the supply
wiring to the circuit breakers, single circuit adaptor kit, or
terminal block. Tighten the lugs securely.
Dual Supply Circuits
When using dual supply circuits verify that the supply
sized for circuit “A” is connected to the circuit breaker
that is connected to the top element assembly.
Replace
metal circuit breaker line cover. Refer to Figure 15 (page
20) for thermostat wiring examples.
Control Board
The control board in the electric furnace controls the
timing sequence of the elements. The board is equipped
with a 3 second blower ON delay and a 15 second blower
OFF delay in heating and a 40 second blower OFF delay
in cooling.
Twinning
Electric furnaces are not supplied with a built in twinning
capability. To connect two electric furnaces to a common
single stage AC condensing unit or heat pump, a twinning
kit is available for field installation.
Please follow the
instructions supplied with the kit.
NOTE:
Variable speed electric furnaces cannot be twinned.
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. Typical AC and electric furnace hookups
are shown in Figure 15 (page 20).
CAUTION:
Isolation must be maintained from the external
Class 2 output of any transformer in a cooling
circuit. Use a thermostat with isolating contacts
to prevent inter-connection of Class 2 outputs.
• Where local codes require that the thermostat wiring
must be routed through a conduit or raceway, splices
can be made inside the unit; however, all wiring must
be NEC Class 1 and must be separated from incoming
power leads.
• The thermostat should be mounted about 5 feet above
the floor 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
fireplaces, sunlight, or lighting fixtures, and convective
heat from warm air registers or electrical appliances.
Refer to the thermostat manufacturer’s instruction sheet
for detailed mounting and installation information.
• Install the grommet, which is packed with the unit, in
the hole for low-voltage wires. Connect the low-voltage
wiring to the thermostat and the outdoor unit and the
appropriate screw terminal located on the control board.
NOTE:
When the low voltage wires are positioned in
this grommet, the grommet will prevent chafing and/or
shorting of the low voltage leads.
Grounding
WARNING:
The unit cabinet must have an uninterrupted
or unbroken electrical ground to minimize
personal injury if an electrical fault should occur.
Do not use gas piping as an electrical ground!
This unit must be electrically grounded in accordance
with local codes or, in the absence of local codes, with
the National Electrical Code (ANSI/NFPA 70) or the CSA
C22.1 Electrical Code. Use the grounding lug provided in
the control box for grounding the unit.
