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I-EEDU (02-21) 150492-A
Electrical Connections
⚠ WARNING ⚠
• If you turn OFF the electrical power supply, turn OFF the gas.
• All electrical wiring and connections, including electrical grounding, MUST be completed in
accordance with local, state, and national codes and regulations and with the National Electric
Code (ANSI/NFPA 70) or in Canada with the Canadian Electrical Code Part 1 C.S.A. C.22.1.
• The installer should be aware of any local ordinances or gas company requirements that might
apply.
⚠ CAUTION ⚠
If any of the unit’s original wire must be replaced, it must be replaced with wiring material having
a temperature rating of at least 105°C, except for sensor lead wires, which must be 150°C.
NOTE: Specific wiring diagrams that include standard and factory-installed options are provided
with the unit. Ensure that all wiring is in accordance with these wiring diagrams.
•
Check the rating plate on the heater for the supply voltage and current requirements .
•
A separate line voltage supply with fused disconnect switch should be run directly from the main electrical panel
to the furnace, making connection to leads in the junction box .
•
The disconnect switch is a required part of this installation . Switches are available, as options or parts, or may be
purchased locally . When ordered as an optional component, the disconnect switch is shipped separately .
•
The disconnect switch may be fusible or non-fusible . When installing the disconnect switch, ensure that the conduit
and switch housing are clear of furnace panels and inspection plates . Allow at least 4 feet (1 .2 meters) of service
room between the switch and removable panels .
•
All external wiring must be within approved conduit and have a minimum temperature rise rating of 60°C . Conduit
from the disconnect switch must be run so as not to interfere with the service panels of the furnace .
FIELD-INSTALLED OPTIONS
NOTE: For control information, refer to the
Controls
section.
Discharge Air Temperature Sensor Installation
All makeup air options (options AG3, AG15, AG8, and AG9) require that the discharge air temperature sensor be
field-installed in the discharge ductwork . Install the sensor in accordance with the following paragraphs .
Option AG3: Discharge Air Temperature Sensor Installation
On units with option AG3 (two-stage makeup air), the unit-mounted ductstat has a capillary tube with a sensor bulb that
must be moved out the way—before installing the ductwork—and then field-installed in the discharge duct as follows:
1 . Ductstat and sensor are connected by permanently-attached capillary tube (see
, DETAIL A) . Before
connecting ductwork, remove capillary tube sensor bulb with bracket from its shipping position on inside of furnace .
2 . Connect ductwork to furnace .
NOTE: Because the sensor is larger than the tubing, a gasket and gasket retainer plate are needed
to plug the hole and to protect the capillary tubing where it passes through the ductwork. These
parts are shipped loose with the furnace (refer to
). Two field-supplied sheet metal screws
are needed to secure the plate.
3 . Follow instructions shown in
