Step 7—Install Electrical Connections
The unit cabinet must have an uninterrupted, unbroken
electrical ground to minimize the possibility of personal
injury if an electrical fault should occur. This ground may
consist of an electrical wire connected to the unit ground lug
in the control compartment, or conduit approved for electrical
ground when installed in accordance with IEC, ANSI/NFPA
American National Standards Institute/National Fire Protec-
tion Association (latest edition) and local electrical codes.
Failure to adhere to this warning could result in serious injury
or death.
Failure to follow these precautions could result in damage to
the unit being installed:
1. Make all electrical connections in accordance with IEC
ANSI/NFPA (latest edition) and local electrical codes
governing such wiring.
2. Use only copper conductor for connections between
field-supplied electrical disconnect switch and unit. DO
NOT USE ALUMINUM WIRE.
3. Be sure that high-voltage power to unit is within operating
voltage range indicated on unit rating plate. On 3-phase
units, ensure phases are balanced within 2 percent. Consult
local power company for correction of improper voltage
and/or phase imbalance.
4. Insulate low-voltage wires for highest voltage contained
within conduit when low-voltage control wires are in same
conduit as high-voltage wires.
5. Do not damage internal components when drilling through
any panel to mount electrical hardware, conduit, etc.
HIGH-VOLTAGE CONNECTIONS
The unit must have a separate electrical service with a field-
supplied, waterproof disconnect switch mounted at, or within sight
from the unit. Refer to the unit rating plate, IEC and local codes for
maximum fuse/circuit breaker size and minimum circuit amps
(ampacity) for wire sizing (See Table 4 for electrical data).
The field-supplied disconnect may be mounted on the unit over the
high-voltage inlet hole (See Figs. 2 and 3).
If the unit has an electric heater, a second disconnect may be
required. Consult the Installation, Start-Up, and Service Instruc-
tions provided with the accessory for electrical service connec-
tions.
Operation of unit on improper line voltage constitutes abuse and
may cause unit damage that could affect warranty.
ROUTING POWER LEADS INTO UNIT
Use only copper wire between disconnect and unit. The high-
voltage leads should be in a conduit until they enter the duct panel;
conduit termination at the duct panel must be watertight. Run the
high-voltage leads through the power entry knockout on the power
entry side panel. (See Fig. 2 and 3 for location and size) When the
leads are inside the unit, run leads up the high-voltage raceway to
the line wiring splice box. (See Fig. 13 through 15) For 3-phase
units, connect the leads to the black, yellow, and blue wires. (See
Fig. 18)
CONNECTING GROUND LEAD TO GROUND LUG
Refer to Fig. 18. Connect the ground lead to the chassis using the
ground lug in the wiring splice box.
ROUTING CONTROL POWER WIRES (24-V)
Form a drip-loop with the thermostat leads before routing them
into the unit. Route the thermostat leads through grommeted,
low-voltage hole provided in unit into unit control power splice
box. (See Fig. 2 and 3) Connect thermostat leads to unit control
power leads as shown in Fig. 17.
The unit transformer supplies 24-v power for complete system
including accessory electrical heater. An automatic-reset circuit
breaker (See Fig. 19) is provided in the 24-v circuit; see the caution
label on the transformer or Fig. 20.
PRE-START-UP
Failure to observe the following warnings could result in
serious personal injury or death:
1. Follow recognized safety practices and wear protective
goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric power to
unit unless compressor terminal cover is in place and
secured.
3. Do not remove compressor terminal cover until all electri-
cal sources are disconnected.
4. Relieve and recover all refrigerant from both high- and
low-pressure sides of system before touching or disturbing
anything inside terminal box if refrigerant leak is suspected
around compressor terminals.
5. Never attempt to repair soldered connection while refrig-
erant system is under pressure.
6. Do not use torch to remove any component. System
contains oil and refrigerant under pressure.
To remove a component, wear protective goggles and
proceed as follows:
a. Shut off electrical power to unit.
b. Relieve and reclaim all refrigerant from system using
both high- and low-pressure ports.
c. Cut component connecting tubing with tubing cutter and
remove component from unit.
d. Carefully unsweat remaining tubing stubs when neces-
sary. Oil can ignite when exposed to torch flame.
Use the Start-Up Checklist supplied at the end of this book and
proceed as follows to inspect and prepare the unit for initial
start-up:
1. Remove all access panels.
Fig. 12—Condensate Trap
C99013
1” (25mm) MIN.
2” (50mm) MIN.
TRAP
OUTLET
11
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