Operating instructions

XI. START-UP, ADJUSTMENT, AND SAFETY CHECK
A. General
The furnace must have a 115-v power supply properly connected
and grounded. Correct polarity must be maintained to enable gas
heating operation.
The gas service pressure must not exceed 0.5 psig (14-in. wc), and
be no less than 0.16 psig (4.5-in. wc).
Thermostat wire connections at R and W/W1 are the minimum
required for gas heating operation. W2 must be connected for
2-stage heating thermostats. Com, Y/Y2, and G are required for
cooling, heat pumps, and some clock thermostats. These must be
made at 24-v terminal block on control. (See Fig. 14.)
This furnace can be installed with either single-stage heating or
2-stage heating thermostat.
For single-stage thermostats, connect thermostat W to W/W1 at
furnace control terminal block. (See Fig. 15.) For single-stage
thermostats the control determines, based on length of previous
heating on and off cycles, when to operate in low- and high-gas
heat for optimum comfort. Setup Switch-2 (SW-2) must be in the
factory-shipped OFF position. See Fig. 17 and Tables 6 and 7 for
setup switch information.
Fig. 14—Control Center
A93348
123
456
78 9
PR2
L2
COM
PR1
L1
EAC-2
EAC-1
HI-COOL
HI-GAS
-HEAT
LO-GAS
-HEAT
PARK
3
FU1
SEC-1 SEC-2
1
123
456
7
8
9
10 11 12
MASTER SLAVE
TWIN
TEST
LED
GRY/Y2W/W1
COM
24 V
W2
1
ON
OFF
1234
FURNACE AND
BLOWER OFF DELAY
SETUP SWITCHES
24-VOLT
THERMOSTAT
TERMINALS
EAC - ELECTRONIC
AIR CLEANER
(115-VAC 1 AMP MAX)
3-AMP
FUSE
LED -
DIAGNOSTIC
LIGHT
TWIN / TEST
TERMINAL
HUM -
HUMIDIFIER
(24-VAC 0.5
AMP MAX)
HUM
TABLE 6—ELECTRICAL DATA
UNIT
SIZE
VOLTS—
HERTZ—
PHASE
OPERATING
VOLTAGE RANGE
MAX
UNIT
AMPS
MIN
WIRE
GAGE
MAX WIRE
LENGTH
FT‡
MAXIMUM
FUSE OR
CKT BKR AMPS†
Max* Min*
024065 115—60—1 127 104 8.0 14 46 15
036065 115—60—1 127 104 10.5 14 35 15
036085 115—60—1 127 104 12.0 14 30 15
048085 115—60—1 127 104 14.2 14 26 15
048105 115—60—1 127 104 13.2 14 29 15
060105 115—60—1 127 104 17.2 12 33 20
060125 115—60—1 127 104 17.9 12 32 20
* Permissible limits of the voltage range at which the unit will operate satisfactorily.
† Time-delay type is recommended.
‡ Length shown is as measured 1 way along wire path between unit and service panel for maximum 2 percent voltage drop.
Fig. 15—Heating and Cooling Application Wiring Diagram With 1-Stage Thermostat and Condensing Unit
A99071
115-V FUSED
DISCONNECT
SWITCH
(WHEN REQUIRED)
JUNCTION
BOX
CONTROL
BOX
24-V
TERMINAL
BLOCK
TWO-WIRE
HEATING-
ONLY
FIVE
WIRE
1-STAGE THERMOSTAT TERMINALS
FIELD-SUPPLIED
FUSED DISCONNECT
CONDENSING
UNIT
FURNACE
COM
R
WYRG
C
GND
GND
GND
GND
GND
GND
FIELD 24-V WIRING
FIELD 115-, 208/230-, 460-V WIRING
FACTORY 24-V WIRING
FACTORY 115-V WIRING
208/230- OR
460-V
THREE
PHASE
208/230-V
SINGLE
PHASE
WHT
BLK
WHT
BLK
W/W1
W2
Y/Y2
G
NOTES: 1. Connect Y-terminal as shown for proper operation.
2. Some thermostats require a "C" terminal connection as shown.
3. If any of the original wire, as supplied, must be replaced,
use same type or equivalent wire.
—12—