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Specifications are subject to change without notice.
21
441 01 1422 00
or ordinances that might apply.
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire.
!
WARNING
Use a separate, fused branch electrical circuit with a properly
sized fuse or circuit breaker for this furnace. See Table 7 for wire
size and fuse specifications. A readily accessible means of
electrical disconnect must be located within sight of the furnace.
NOTE
: Proper polarity must be maintained for 115
−
v wiring. If
polarity is incorrect, control LED status indicator light will flash a
status code 10 and furnace will NOT operate.
J
−
BOX RELOCATION
NOTE
: If factory location of J
−
Box is acceptable, go to next
section (ELECTRICAL CONNECTION TO J
−
BOX).
NOTE
: On 14
−
in. (356 mm) wide casing models, the J
−
Box
shall not be relocated to other side of furnace casing when the
vent pipe is routed within the casing.
1. Remove and save two screws holding J
−
Box.
NOTE
: The J
−
Box cover need not be removed from the J
−
Box
in order to move the J
−
Box. Do NOT remove green ground
screw inside J
−
Box.
2. Cut wire tie on loop in furnace wires attached to J
−
box.
3. Move J
−
Box to desired location.
4. Fasten J
−
Box to casing with two screws removed in Step 1.
5. Route J
−
Box wires within furnace away from sharp edges,
rotating parts and hot surfaces.
ELECTRICAL CONNECTION TO J
−
BOX
Electrical Box on Furnace Casing Side
FIRE OR ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
If field
−
supplied manual disconnect switch is to be mounted
on furnace casing side, select a location where a drill or
fastener cannot damage electrical or gas components.
!
WARNING
1. Select and remove a hole knockout in the casing where the
electrical box is to be installed.
NOTE
: Check that duct on side of furnace will not interfere with
installed electrical box.
2. Remove the desired electrical box hole knockout and posi-
tion the hole in the electrical box over the hole in the fur-
nace casing.
3. Fasten the electrical box to casing by driving two field
supplied screws from inside electrical box into casing
steel.
4. Remove and save two screws holding J
−
Box.
5. Pull furnace power wires out of 1/2
−
in. (12 mm) diameter
hole in J
−
Box. Do not loosen wires from strain
−
relief
wire
−
tie on outside of J
−
Box.
6. Route furnace power wires through holes in casing and
electrical box and into electrical box.
7. Pull field power wires into electrical box.
8. Remove cover from furnace J
−
Box.
9. Route field ground wire through holes in electrical box
and casing, and into furnace J
−
Box.
10. Reattach furnace J
−
Box to furnace casing with screws re-
moved in Step 4.
11. Secure field ground wire to J
−
Box green ground screw.
12. Complete electrical box wiring and installation. Connect
line voltage leads as shown in Fig. 25. Use best practices
(NEC in U.S. for wire bushings, strain relief, etc.)
13. Reinstall cover to J
−
Box. Do not pinch wires between
cover and bracket.
POWER CORD INSTALLATION IN FURNACE J
−
BOX
NOTE
: Power cords must be able to handle the electrical
requirements listed in Table 7. Refer to power cord
manufacturer’s listings.
1. Remove cover from J
−
Box.
2. Route listed power cord through 7/8
−
in. (22 mm) diameter
hole in J
−
Box.
3. Secure power cord to J
−
Box bracket with a strain relief
bushing or a connector approved for the type of cord used.
4. Secure field ground wire to green ground screw on J
−
Box
bracket.
5. Connect line voltage leads as shown in Fig. 25.
6. Reinstall cover to J
−
Box. Do not pinch wires between
cover and bracket.
BX CABLE INSTALLATION IN FURNACE J
−
BOX
1. Remove cover from J
−
Box.
2. Route BX cable into 7/8
−
inch diameter hole in J
−
Box.
3. Secure BX cable to J
−
Box bracket with connectors ap-
proved for the type of cable used.
4. Secure field ground wire to green ground screw on J
−
Box
bracket.
5. Connect line voltage leads as shown in Fig. 25.
6. Reinstall cover to J
−
Box. Do not pinch wires between
cover and bracket.
A10141
Fig. 23
−
Field
−
Supplied Electrical Box on Furnace Casing
24
−
V WIRING
Make field 24
−
v connections at the 24
−
v terminal strip. (See Fig.
25.) Connect terminal Y as shown in Fig. 24 for proper cooling
operation. Use only AWG No. 18, color
−
coded, copper thermostat
wire.
The 24
−
v circuit contains an automotive
−
type, 3
−
amp. fuse located
on the control. Any direct shorts during installation, service, or