7
Low Voltage
High Voltage
Strip Heat Voltage
Figure 7. Power Entry
• Units are shipped from the factory wired for 230 volt transformer
operation. For 208V operation, remove the lead from the
transformer terminal marked 230V and connect it to the
terminal marked 208V.
• 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.
Overcurrent Protection
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 and maximum overcurrent protection
limits. Generally, the best fuse or breaker for any air conditioner
is the smallest size that will permit the equipment to run under
normal usage and provide maximum equipment protection.
Properly sized fuses and breakers also prevent nuisance trips
during unit startup.
If a fuse blows or a breaker trips, always
determine the reason. Do not arbitrarily install a larger fuse
or breaker and do not, in any case, exceed the maximum
size listed on the data label of the unit.
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 CSA C22.1 Electrical Code.
Ground the air conditioning unit using the green grounding screw
provided in the control panel.
Thermostat / Low Voltage Connections
• The 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. Thermostat connections should
be made in accordance with the instructions supplied with the
thermostat and the indoor equipment.
• The low voltage wires must be properly connected. Route 24V
control wires through the sealing grommet near the power
entrance. See
. Recommended wire
gauge and wire lengths for typical thermostat connections
are listed in
.
ELECTRICAL CONNECTIONS
WARNING:
ELECTRICAL SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Before servicing, disconnect all electrical power
to the indoor blower.
• When servicing controls, label all wires prior
to disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
• 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 high and low voltage wiring.
√
Verify factory wiring is in accordance with the unit wiring
diagram
.
Inspect for loose connections.
Line Voltage
• A wiring diagram is located on the inside cover of the electrical
box of the unit. The installer should become familiar with the
wiring diagram before making any electrical connections to
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 field wiring. Any other wiring
methods must be acceptable to authority having jurisdiction.
• 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 unit data label. Any other wiring
methods must be acceptable to authority having jurisdiction.
• 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. Extend leads through power wiring
L1 & L2 directly to the contactor.
• The unit requires both power and control circuit electrical
connections. Refer to the wiring diagrams (
) for identification and location
of unit field wiring interfaces. Make all electrical connections
in accordance with all applicable codes and ordinances.
• 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. Use of
rain tight conduit is recommended.
