INTERIOR MAKE-UP BOX INSTALLATION
Right Side
BOX
FIGURE 28
Refer to figure 29 for schematic wiring diagram, field wiring and trouble shooting.
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.
NOTE - Unit nameplate states maximum current draw. Maximum
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 and field wiring diagram shown in fig ure 29. Use
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
NOTE - The EL180UHE 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 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 neutral terminals. If an accessory rated at greater than one amp is connected to this terminal, it is necessary to use an exter nal 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 humidi fier rated at greater than one amp is connected to this termi nal, it is necessary to use an external relay relay.
One 24V ”H” 1/4” spade terminal is provided on the furnace integrated control. See figure 30 for integrated control con figuration. The terminal is energized in the heating mode when the combustion air inducer is operating and the pres sure switch is closed. Any humidifier rated up to 0.5 amp can be connected to this terminal with the ground leg of the circuit connected to ground or the ”C” terminal.
Generator Use - Voltage Requirements
The following requirements must be kept in mind when specifying a generator for use with this equipment:
SThe furnace requires 120 volts + 10% (Range: 108 volts to 132 volts).
SThe furnace operates at 60 Hz + 5% (Range: 57 Hz to 63 Hz).
SThe 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.
SGenerator should have a wave form distortion of less than 5% total harmonic distortion.
Thermostat
Install the room thermostat according to the instructions provided with the thermostat. See figure 29 for thermostat designations. If the furnace is being matched with a heat pump, refer to the FM21 installation instruction or appropri ate dual fuel thermostat instructions.
Indoor Blower Speeds
1 - When the thermostat is set to “FAN ON,” the indoor blower will run continuously on the fan speed when there is no cooling or heating demand.
2 - When the EL180UHE is running in the heating mode, the indoor blower will run on the heating speed.
3 - When there is a cooling demand, the indoor blower will run on the cooling speed.
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