Installation Manual

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Specifications subject to change without notice.
2. Route listed power cord through 7/8-- in. (22 mm) diameter
hole in casing and J-- Box bracket.
3. Secure power cord to J--Box bracket with a strain relief
bushing or a connector approved for the type of cord used.
4. Pull furnace power wires through 1/2 --in. (12 mm) diameter
hole in J --Box. If necessary, loosen power wires from
strain—relief wire--tie on furnace wiring harness.
5. Connect field ground wire and factory ground wire to green
ground screw on J-- Box mounting bracket as shown in Fig.
34.
6. Connect power cord power and neutral leads to furnace
power leads as shown in Fig. 32.
7. Attach furnace J--Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires be-
tween cover and bracket. See Fig. 34.
BX Cable Installation in Furnace J --Box
1. Install J--Box mounting bracket to inside of furnace casing.
See Fig. 34.
2. Route BX connector through 7/8--in. (22 mm) diameter
hole in casing and J-- Box bracket.
3. Secure BX cable to J--Box bracket with connectors ap-
proved for the type of cable used.
4. Connect field ground wire and factory ground wire to green
ground screw on J-- Box mounting bracket as shown in Fig.
34.
5. Connect field power and neutral leads to furnace power
leads. as shown in Fig. 32.
6. Attach furnace J--Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires be-
tween cover and bracket.
FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in dangerous
operation, personal injury, death, or property damage.
Do not drill into blower shelf of furnace to route control
wiring. Route any control or accessory wiring to the blower
compartment through external knockouts on the casing.
!
WARNING
Communication Connector is used when the furnace is controlled
by an optimum communicating User Interface. See Fig. 36.
The communication plug is supplied with the User Interface. Refer
to the instructions supplied with the User Interface.
ABCD
A03193
Fig. 36 -- Communication Connector
Outside Air Thermistor (OAT)
Used in conjunction with communicating User Interface. Not
required when a standard type thermostat is used. Refer to the
instructions supplied with the User Interface for details.
24--V Wiring
Make field 24--v connections at the 24--v terminal strip. See Fig.
38. Connect terminal Y/Y2 as shown in Fig. 32 for proper cooling
operation. Use only AWG No. 18, color-- coded, copper thermostat
wire.
NOTE: Use AWG No. 18 color-coded copper thermostat wire for
lengths up to 100 ft. (30 M). For wire lengths over 100 ft., use
AWG No. 16 wire.
The 24--v circuit contains an automotive--type, 3--amp. fuse located
on the control. Any direct shorts during installation, service, or
maintenance could cause this fuse to blow . If fuse replacement is
required, use ONLY a 3 -- amp. fuse of identical size. See Fig. 38.
Thermostats
A single stage heating and cooling thermostat can be used with the
furnace. The furnace control board CPU will control the furnace
and outdoor unit staging. A two stage heating and cooling
thermostat can also be used to control the staging. For two stage
thermostat control of the furnace staging, turn SW1-2 ON at the
furnace control board. For two stage thermostat control of a 2-stage
outdoor unit, remove the ACRDJ jumper from the furnace control
board. Refer to typical thermostat wiring diagrams and the
Sequence of Operation section for additional details. Consult the
thermostat installation instructions for specific information about
configuring the thermostat. See Fig. 38 and 39.
A11157
Fig. 37 -- Field--supplied Isolation Relay for Humidifiers with Internal Power Supply