SYSTEM OPERATION
6
ELECTRICAL CONNECTIONS
WARNING
High Voltage!
To avoid the risk of electrical shock,
wiring to the unit must be polarized and
grounded.
WARNING
High Voltage!
To avoid personal injury or death
due to electrical shock, disconnect
electrical power before servicing or
changing any electrical wiring.
CAUTION
Label all wires prior to disconnection when
servicing controls. Wiring errors can cause
improper and dangerous operation. Verify
proper operation after servicing.
Wiring Harness
The wiring harness is an integral part of this furnace.
Wires are color coded for identification purposes. Refer to
the wiring diagram for wire routings. If any of the original
wire as supplied with the furnace must be replaced, it must
be replaced with wiring material having a temperature
rating of at least 105° C. Any replacement wiring must be a
copper conductor.
115 Volt Line Connections
Before proceeding with electrical connections, ensure that
the supply voltage, frequency, and phase correspond to
that specified on the unit rating plate. Power supply to
the furnace must be NEC Class 1, and must comply with
all applicable codes. The furnace must be electrically
grounded in accordance with local codes or, in their
absence, with the latest edition of The National Electric
Code, ANSI NFPA 70 and/or The Canadian Electric Code
CSA C22.1.
Use a separate fused branch electrical circuit containing
properly sized wire, and fuse or circuit breaker. The fuse
or circuit breaker must be sized in accordance with the
maximum overcurrent protection specified on the unit rating
plate. An electrical disconnect must be provided at the
furnace location.
Connect hot, neutral, and ground wires as shown in the
wiring diagram located on the unit’s blower door. For
direct vent applications, the cabinet opening to the junction
box must be sealed air tight using either an UL approved
bushing such as Heyco Liquid Tight or by applying non-
reactive UL approved sealant to bushing.
Line polarity must be observed when making field
connections. Line voltage connections can be made
through either the right or left side panel. The furnace
is shipped configured for a left side (right side for
counterflows) electrical connection with the junction box
located inside the burner compartment. To make electrical
connections through the opposite side of the furnace, the
junction box must be relocated to the other side of the
burner compartment prior to making electrical connections.
To relocate the junction box, follow the steps shown below.
NOTE: Wire routing must not to interfere with
circulator blower operation, filter removal, or
routine maintenance.
Junction Box Relocation
WARNING
Edges of sheet metal holes may be sharp. Use
gloves as a precaution when removing hole
plugs.
WARNING
To prevent personal injury or death due to
electric shock, disconnect electrical power
before installing or servicing this unit.
Line voltage connections can be made through either the
right or left side panel. The furnace is shipped configured
for a left side electrical connection. To make electrical
connections through the opposite side of the furnace, the
junction box must be relocated to the right side prior to
making electrical connections. To relocate the junction box,
perform the following steps.
1. Remove the burner compartment door.
2. Remove and save the two screws securing the junction
box to the side panel.
3. Relocate junction box and associated plugs and
grommets to opposite side panel. Secure with screws
removed in step 2.
To ensure proper unit grounding, the ground wire should
run from the furnace ground screw located inside the
furnace junction box all the way back to the electrical panel.
