508144-01
Issue 2128
Page 23 of 42
Failure to use properly sized wiring and circuit breaker
may result in property damage. Size wiring and circuit
breaker(s) per Technical Specification and unit rating
plate.
CAUTION
The unit is equipped with a field make-up box on the left
hand side of the cabinet. The make-up box may be moved
to the right side of the furnace to facilitate installation. If
the make-up box is moved to the right side, clip the wire
ties that bundle the wires together. The excess wire must
be pulled into the blower compartment. Secure the excess
wire to the existing harness to protect it from damage.
Refer to Figure 32 for schematic wiring diagram and
troubleshooting.
The power supply wiring must meet Class I restrictions.
Protected by either a fuse or circuit breaker, select circuit
protection and wire size according to unit nameplate.
Figure 30.
Interior Make-Up Box Installation
Figure 31.
Interior Make-Up Box Installation
NOTE:
Unit nameplate states maximum current draw.
Maximum over current protection allowed is 15 AMP.
Holes are on both sides of the furnace cabinet to facilitate
wiring.
Install a separate (properly sized) disconnect switch near
the furnace so that power can be turned off for servicing.
Before connecting the thermostat, check to make sure the
wires will be long enough for servicing at a later date. Make
sure that thermostat wire is long enough to facilitate future
removal of blower for service.
Complete the wiring connections to the equipment. Use
the provided unit wiring diagram shown in Figure 32. Use
18 gauge wire or larger that is suitable for Class II rating for
thermostat connections.
Electrically ground the unit according to local codes or,
in the absence of local codes, according to the current
National Electric Code (ANSI/NFPA No. 70). A green
ground wire is provided in the field make-up box.
NOTE:
This furnace contains electronic components that
are polarity sensitive. Make sure that the furnace is wired
correctly and is properly grounded.
Accessory Terminals
One line voltage “EAC” 1/4” spade terminal is provided on
the furnace integrated control. See Figure 33 for integrated
control configuration. This terminal is energized when the
indoor blower is operating. Any accessory rated up to one
amp can be connected to this terminal with the neutral
leg of the circuit being connected to one of the provided
neutral terminals. If an accessory rated at greater than one
amp is connected to this terminal, it is necessary to use an
external relay.
One line voltage “HUM” 1/4” spade terminal is provided
on the furnace integrated control. See Figure 33 for
integrated control configuration. This terminal is energized
in the heating mode when the combustion air inducer is
operating. Any humidifier rated up to one amp can be
connected to this terminal with the neutral leg of the circuit
being connected to one of the provided neutral terminals. If
a humidifier rated at greater than one amp is connected to
this terminal, it is necessary to use an external relay.
Generator Use - Voltage Requirements
The following requirements must be kept in mind when
specifying a generator for use with this equipment:
•
The furnace requires 120 volts ± 10% (Range: 108
volts to 132 volts).
•
The furnace operates at 60 Hz ± 5% (Range: 57 Hz
to 63 Hz).
•
The furnace integrated control requires both polarity
and proper ground. Both polarity and proper grounding
should be checked before attempting to operate the
furnace on either permanent or temporary power.
•
Generator should have a wave form distortion of less
than 5% RHO.
