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Line Voltage Wiring
The line voltage (115 volt) to the furnace must
be supplied from a dedicated branch circuit
containing the correct fuse or circuit breaker for
the furnace. See Table 11. An electrical switch
should be readily accessible from and within
sight of the furnace. (See the Wiring Diagram
label in the furnace and Figure 25.)
The furnace cabinet must have an uninter-
rupted, unbroken ground to minimize injury
should an electrical fault condition occur. The
controls used in this furnace require an earth
ground to operate properly. Acceptable meth-
ods for grounding are electrical wire or conduit
approved for electrical ground service. Do not
use gas piping as an electrical ground.
NOTE: Proper line voltage polarity must be
maintained in order for the control system
to operate correctly. Verify that the incom-
ing neutral line is connected to the white
wire and the incoming "hot" line is con-
nected to the black wire in the junction box.
These furnaces will not operate unless po-
larity and ground are properly connected.
See Figure 25.
!
CAUTION:
Label all wires prior to disconnection
when servicing controls. Wiring errors
can cause improper and dangerous
operation. Verify proper operation af-
ter servicing.
Furnace
Cabinet
Input
Width
(Btuh)
(in.)
60,000
19.75
80,000
19.75
92,000
19.75
110,000
22.50
* Time-delay fuses or HACR-type circuit breakers are required.
32
NOTE: The following procedure describes how
to connect the furnace for a two-stage application.
Low Voltage Wiring
Staging Configurations
These furnaces are factory configured to oper-
ate on high fire only, but can be field converted
to operate as two-stage furnaces.
NOTE:
efficiency, the furnace should be operated in the
factory configuration (high fire only as described
in part 2.)
1.
2.
Nominal
Maximum
Electrical
Operating Operating
Supply
Voltage
115-60-1
127
115-60-1
127
115-60-1
127
115-60-1
127
Thermostat
Recommended Thermostat
Wire
Wire Length
Gauge
2-wire
(heating)
24
55 ft.
22
90 ft.
20
140 ft.
18
225 ft.
Table 11. Electrical Data
T
achieve full rated capacity and
O
Two stage heating thermostat configura-
tion – For this installation a two stage
heating thermostat is used. CAUTION:
Disconnect yellow wire with black stripe
from low firing on the gas valve. Remove
female connector from yellow/black wire
and strip insulation from end. Connect
stripped yellow wire with black stripe to
(W2) from the thermostat. (See Figure
26a). The first stage bulb (W1) is connected
to W on the furnace control board. On a call
for first stage heat, the furnace will operate
at low fire and the blower will run at a lower
speed. On a call for second stage heat, the
furnace will operate at high fire and the
blower will run at a higher speed. The
furnace will stage between low fire, high fire,
and off depending on the thermostat signal.
High fire only configuration – As shipped
from the factory, low and high terminals on
the gas valve are connected in parallel
(See Figure 26b). This defeats the staging
Minimum
Maximum
Minimum
Furnace
Wire
Voltage
Amperes
Gauge
103
12
103
12
103
12
103
12
4 or 5-wire
(cooling)
25 ft.
45 ft.
70 ft.
110 ft.
Maximum
Fuse or Circuit
Breaker Amps*
14
15
14
15
14
15
14
15
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