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NEC — National Electrical Code
Power Wiring
Control Wiring
*Required for electric heater when single-point connection is not
used.
Fig. 12 — Typical Installation
C. Converting Horizontal Discharge Units to Downflow
(Vertical) Discharge
WARNING: Before performing service or mainte-
nance operations on system, turn off main power to unit.
Turn off accessory heater power switch if applicable. Elec-
trical shock can cause personal injury.
Units are dedicated side-supply products. Units are not con-
vertible to vertical air supply. A field-supplied plenum must
be used to convert to vertical air discharge.
D. Electrical Connections
WARNING: The unit cabinet must have an un-
interrupted, unbroken electrical ground to minimize the
possibility of personal injury if an electrical fault should
occur. This ground may consist of an electrical wire con-
nected to the unit ground in the control compartment,
or conduit approved for electrical ground when
installed in accordance with NEC, ANSI (American
National Standards Institute)/NFPA (latest edition)
(in Canada, Canadian Electrical Code CSA [Canadian
Standards Association] C22.1) and local electrical codes.
Failure to adhere to this warning could result in per-
sonal injury or death.
LEGEND
Outdoor Airflow
Indoor Airflow
CAUTION: Failure to follow these precautions could
result in damage to the unit being installed:
1. Make all electrical connections in accordance with
NEC ANSI/NFPA (latest edition) and local electrical
codes governing such wiring. In Canada, all elec-
trical connections must be in accordance with CSA
Standard C22.1 Canadian Electrical Code Part 1
and applicable local codes. Refer to unit wiring
diagram.
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 op-
erating voltage range indicated on unit rating plate.
On 3-phase units, ensure that phases are balanced
within 2%. Consult local power company for correc-
tion of improper voltage and/or phase imbalance.
4. Insulate low-voltage wires for highest voltage con-
tained within conduit when low-voltage control wires
are run in same conduit as high-voltage wires.
5. Do not damage internal components when drilling
through any panel to mount electrical hardware, con-
duit, 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 for maxi-
mum fuse/circuit breaker size and minimum circuit amps
(ampacity) for wire sizing. See Table 2 for electrical data.
The field-supplied disconnect may be mounted on the unit over
the high-voltage inlet hole. See Fig. 2-4.
CAUTION: Operation of unit on improper line volt-
age 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 unit;
conduit termination at the unit must be watertight. Run the
high-voltage leads through the hole on the side of the unit
(see Fig. 13 for location). When the leads are inside the unit,
run leads to the control box (Fig. 14). For single-phase units,
connect leads to the black and yellow wires; for 3-phase units,
connect the leads to the black, yellow, and blue wires (see
Fig. 15).
Connecting Ground Lead to Unit Ground
Refer to Fig. 14 and 15. Connect the ground lead to the chas-
sis using the unit ground screw in the control box.
Routing Control Power Wires
Form a drip-loop with the thermostat leads before routing
them into the unit. Route the thermostat leads through
grommeted hole provided in unit (see Fig. 13) into unit con-
trol box. Connect thermostat leads to unit control power leads
as shown in Fig. 16.
—8—
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