14
Proper line voltage polarity must be maintained in
order for the control system to operate correctly.
Verify the incoming neutral line is connected to the
white wire and the incoming “hot” line is connected
to the black wire. The furnace will not operate unless
the polarity and ground are properly connected as
shown in Figure 12 or the wiring diagram label inside
of the control door.
Furnace
Model
Number
G7XA
Furnace
Input
(Btu/hr)
Cabinet
Width
(in.)
Nominal
Electrical
Supply
Maximum
Operating
Voltage
Minimum
Operating
Voltage
Maximum
Furnace
Amperes
Minimum
Wire
Gauge
Maximum
Fuse or Circuit
Breaker Amps**
046-23A
46,000
14
¼
230-50-1
230
208
6.3
14
15
061-24B
61,000
17
½
230-50-1
230
208
9.7
14
20
076-24B
76,000
17
½
230-50-1
230
208
9.7
14
20
092-35C
92,000
21
230-50-1
230
208
11.7
14
20
107-45D
107,000
24
½
230-50-1
230
208
15.2
12
30
** Time-delay fuses or HACR-type circuit breakers are required.
Thermostat Wire Gauge
Recommended Thermostat Wire Length
2 - wire
(Heating only)
4 or 5 wire
(Heating/Cooling)
24
55 ft.
25 ft.
22
90 ft.
45 ft.
20
140 ft.
70 ft.
18
225 ft.
110 ft.
Table 2. Wire Length and Voltage Specifi cations
FURNACE
W
G
Y
C
R
THERMOSTAT
W
G
Y
C
R
W
G
Y
R
A/C
MOTOR
TWIN TERMINAL
BOARD
UNIT
BOARD
FURNACE
BOARD
MOTOR
TWIN TERMINAL
BOARD
FURNACE 1
FURNACE 2
Figure 13. Twinning
Figure 12. Line Voltage Field Wiring
Field Supplied
Disconnect w/in
Sight of Furnace
Field Supplied
Panel Connector
Field Supplied
Fused Service
Panel
Black (Hot)
White (Neutral)
Green or Bare
(Ground)
Black
White
Black
White
Black
White
Field Line Voltage Wiring
Factory Line Voltage Wiring
Ground
Ground
Junction Box (may be int. or ext.
to the furnace). These connections
can be made in the field supplied
disconnect at the furnace.
Ground
Twinning
The control boards on fi xed speed furnaces are capable
of being twinned to other furnaces of the same series,
only if the following criteria are met:
• The circuit boards are the same.
• The thermostat wires and the 1/4 inch thick quick-connect
terminals marked
“TWIN”
(Figure 13) on the furnace
controls must be connected together.
• The fuses must remain installed on each board.
• Twinned furnaces must be properly grounded according
to local codes.
IMPORTANT NOTE: G7 furnaces equipped with
variable speed iSEER™ motors may not be twinned
under any circumstances.
Summary of Contents for G7XA Series
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