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.
• All 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 specifications on the unit rating plate.
√
Verify that the service provided by the utility is sufficient
to handle the additional load imposed by this equipment.
Refer to the unit wiring label for proper voltage wiring.
√
If replacing an existing unit, verify that the: current wiring,
unit disconnect and circuit breaker is properly sized and
rated for the new units requirements. Verify that information
with the MCA and MOP values on the unit nameplate.
√
Verify factory wiring is in accordance with the unit wiring
diagrams
Inspect for loose connections.
Line Voltage
• A wiring diagram is located on the inside cover of the
electrical box of the outdoor unit. The installer should
become familiar with the wiring diagram before making
any electrical connections to the outdoor 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.
• Line voltage to the unit should be supplied from a dedicated
branch circuit containing the correct fuse or circuit breaker
for the unit. Incoming field wiring and minimum size of
electrical conductors and circuit protection must be in
compliance with information listed on the outdoor unit
data label. Any other wiring methods must be acceptable
to authority having jurisdiction.
• The outdoor unit requires electrical connections for its
incoming line voltage wiring, its safety ground wiring and
the low voltage control circuit wiring. Refer to the wiring
diagram for identification and location of outdoor unit field
wiring interfaces
. Make all electrical connections in accordance with all
applicable codes and ordinances.
• 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 minimum circuit ampacity (MCA)
and maximum overcurrent protection (MOP) limits.
• Provide power supply for the unit in accordance with the
unit wiring diagram, and the unit rating plate. Connect the
line-voltage leads to the terminals on the contactor inside
the control compartment.
• Use only copper wire for the line voltage power supply to
this unit in strict accordance of the NEC (ANSI/NFPA 70),
applicable local codes, and the instructions provided with
the equipment. Use proper code agency listed conduit
and a conduit connector for connecting the supply wires
to the unit. Use of rain tight conduit is recommended.
• Optional equipment requiring connection to the power or
control circuits must be wired in strict accordance of the
NEC (ANSI/NFPA 70), applicable local codes, and the
instructions provided with the equipment.
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.
Thermostat Connections
• Thermostat connections should be made in accordance
with the instructions supplied with the thermostat and the
indoor equipment.
Low Voltage Connections
• The outdoor unit is designed to operate from a 24 VAC
Class II control circuit. The control circuit wiring must comply
with the current provisions of the NEC (ANSI/NFPA 70)
and with applicable local codes having jurisdiction.
• The low voltage wires must be properly connected to the
units low voltage terminal block.
• For applications utilizing the outdoor thermostatic switch
within these units, the installer shall need to wire in
the switch as appropriate for their application. Refer to
for typical configurations and the unit wiring
diagram as needed.
Thermostat
Red
White
Black
Air Handler
Outdoor
Heat
Pump
OUT
IN
R
W
C
O
Y
R
G
C
O
Y
O
C
R
W2
W2
Y1
IN
Green
G
W2
E
ODT
(Optional)
Figure 3. Typical Thermostat Connections
