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Complete the wiring connections to the equipment. Use
the provided unit wiring diagram and the field wiring dia
-
gramshown in figure 29. 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 Na-
tional Electric Code (ANSI/NFPA No. 70). A green ground
wire is provided in the field make-up box.
NOTE -
The EL280UH furnace contains electronic com
-
ponents that are polarity sensitive. Make sure that the fur
-
nace 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 30 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 neu-
tral 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 30 for integrated
control configuration. This terminal is energized in the
heating mode when the combustion air inducer is operat-
ing. Any humidifier rated up to one amp can be connected
to this terminal with the neutral leg of the circuit being con-
nected to one of the provided neutral terminals.If a hu-
midifier rated at greater than one amp is connected to this
terminal, it is necessary to use an external relay 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 po-
larity and proper ground. Both polarity and proper
grounding should be checked before attempting to
operate the furnace on either permanent or tempo-
rary power.
• Generator should have a wave form distortion of
less than 5% total harmonic distortion (THD).
Thermostat
Install the room thermostat according to the instructions
provided with the thermostat. See table 7 for thermostat
designations. If the furnace is being matched with a heat
pump, refer to the FM21 installation instruction or appro-
priate dual fuel thermostat instructions.
Indoor Blower Speeds
1 - When the thermostat is set to “FAN ON,” the indoor
blower will run continuously on the low speed when
there is no cooling or heating demand.
2 -
When the EL280UH is operating in the high-fire or
lowfire heating mode, the indoor blower will run on
the corresponding heating speed.
3 - When the EL280UH is operating in the low cool or
the high cool cooling mode, the indoor blower will
run on the corresponding cooling speed.
