Payne C Series Installation, Start-Up, Operating And Service And Maintenance Instructions page 35

CAUTION
!
FURNACE MAY NOT OPERATE HAZARD
Failure to follow this caution may result in intermittent
furnace operation.
Furnace control must be grounded for proper operation or
else control will lock out. Control must remain grounded
through green/yellow wire routed to gas valve and manifold
bracket screw.
115−V Wiring
Furnace must have a 115-v power supply properly connected and
grounded.
NOTE: Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, control LED status indicator light will flash
rapidly and furnace will NOT operate.
Verify that the voltage, frequency, and phase correspond to that
specified on unit rating plate. Also, check to be sure that service
provided by utility is sufficient to handle load imposed by this
equipment. Refer to rating plate or Table 12 for equipment
electrical specifications.
U.S.A. Installations: Make all electrical connections in accordance
with the current edition of the National Electrical Code (NEC)
NFPA 70 and any local codes or ordinances that might apply.
Canada Installations: Make all electrical connections in
accordance with the current edition of the Canadian Electrical
Code CSA C22.1 and any local codes or ordinances that might
apply.
WARNING
!
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. See Fig. 37.
Use a separate, fused branch electrical circuit with a properly sized
fuse or circuit breaker for this furnace. See Table 12 for wire size
and fuse specifications. A readily accessible means of electrical
disconnect must be located within sight of the furnace.
J−Box Installation
WARNING
!
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.
The J−Box is used when field line voltage electrical connections
are made to the furnace wiring harness inside the furnace casing.
The J−Box cover is not required if a field−supplied external
electrical box is attached to the outside of the furnace casing. The
field wiring and main wiring harness are grounded with the furnace
box is grounded to the green ground screw of the J−Box bracket
and the earth ground of the field electrical supply.
The J−Box cover, mounting bracket and screws are shipped in the
loose parts bag included with the furnace. See Fig. 36 for J−Box
mounting locations.
The J−Box mounting bracket and green ground screw is used as a
grounding point for all line voltage wiring options. The J−Box
cover may be omitted when electrical connections are made inside
an external electrical box mounted external to the casing.
External Electrical Box on Furnace Casing
NOTE: Check to ensure that external electrical box does not
interfere with duct work, gas piping or the indoor coil drain. See
Fig. 34 for alternate electric entry through top panel.
1. Select and remove 7/8−in. (22 mm) knock−out on the
desired side of the casing. Remove the knock−out from the
casing.
NOTE: If electrical entry through the furnace top panel is used, a
7/8−in. (22 mm) hole must be drilled through the top panel.
2. Drill two (2) 1/8−in. (3 mm) pilot holes through the dimples
in the furnace casing near the 7/8−in. knock−out.
NOTE: If electrical entry through the furnace top panel is used,
mark the screw hole locations using the mounting holes in the
external electrical box as a template.
For a side−mounted external electrical box, complete the
following:
1. Align the J−Box bracket with the knock−out inside the
furnace casing.
2. Install the threaded end of a strain−relief bushing through
the J−Box bracket and the furnace casing. Strain−relief
bushing should be installed so that the bushing can be
tightened around the wiring harness inside the furnace
casing.
3. Align the external electrical box with the 7/8−in. (22 mm)
knock−out.
4. Install and tighten the lock−nut on the strain−relief bushing
inside the external electrical box.
5. Fasten the external electrical box to the furnace casing using
two (2) sheet metal screws.
6. Route field power wiring into external electrical box.
7. Pull furnace line voltage power wires through strain−relief
bushing of the external electrical box.
8. Pull the ground wire of the field line voltage wiring through
the strain−relief bushing into the furnace casing.
9. Install the green ground screw to the J−Box bracket and
attach both ground wires to the green ground screw.
10. Connect any code required external disconnect(s) to field
power wiring.
11. Connect field power and neutral leads to furnace power
leads inside the external electrical box as shown in Fig. 32.
For a top panel−mounted external electrical box, complete the
following:
1. Drill two (2) 1/8−in. (3 mm) pilot holes through the dimples
in the furnace casing near the 7/8−in. knock−out on the side
of the casing. Do not remove the knock−out in the side of
the casing.
2. Align the J−Box bracket with the pilot holes inside the
furnace casing.
3. Install 2 screws through the outside of the casing to secure
the J−Box bracket to the furnace casing.
4. Route field power wiring into external electrical box.
5. Pull furnace line voltage power wires through strain−relief
bushing of the external electrical box.
6. Pull the ground wire of the field line voltage wiring through
the strain−relief bushing into the furnace casing.
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