ROUTING POWER LEADS INTO UNIT — Use only cop-
per wire between disconnect and unit. The high-voltage leads
should be in a conduit until they enter the duct panel; con-
duit termination at the duct panel must be watertight. Run
the high-voltage leads through the knockout on the duct panel
(see Fig. 23 for location and size). When the leads are inside
the unit, run leads up the high-voltage raceway to the line
wiring splice box (Fig. 24). For single-phase units, connect
leads to the black and yellow wires; for 3-phase units, con-
nect the leads to the black, yellow, and blue wires (see
Fig. 25).
CONNECTING GROUND LEAD TO GROUND LUG —
Refer to Fig. 24 and 25. Connect the ground lead to the chas-
sis 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 hole
provided in unit into unit control power splice box. See
Fig. 23. Connect thermostat leads to unit control power leads
as shown in Fig. 26.
The unit transformer supplies 24-v power for complete
system including accessory electrical heater. An automatic-
reset circuit breaker is provided in the 24-v circuit; see the
caution label on the transformer or Fig. 27. Transformer
is factory wired for 230-v operation. If supply voltage is
208 v, rewire transformer primary as described in the
following section.
1 3/8
″
DIA.
1 1/8
″
DIA.
POWER
ENTRY
2
″
DIA.
2
″
DIA.
7/8
″
DIA.
LOW VOLTAGE
ENTRY
NOTE: Knockout sizes are for round-duct units. For rectangular duct
unit dimensions, see Fig. 4 and 5.
Fig. 23 — Duct Panel Knockouts
UNIT LINE WIRE
SPLICE BOX
UNIT POWER
LEAD
CONTROL POWER
SPLICE BOX
GROUND
LUG
Fig. 24 — Wiring Splice Boxes
LEGEND
NEC — National Electrical Code
Splice Connections
Field Wiring
NOTE: Use copper wire only.
Fig. 25 — Line Power Connections
Fig. 26 — Control Connections
Fig. 27 — Transformer Label
16
