Step 10—Start-up, Adjustment, and Safety Check
GENERAL
NOTE:
Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, control center fault indicator light will flash
rapidly and furnace will not operate.
The furnace must have a 115-v power supply properly connected
and grounded. Proper polarity must be maintained for correct
operation. Thermostat wire connections at R, W, C, and Y must be
made at the 24-v terminal block on the control board. The gas
service pressure must not exceed 0.5 psig (14-in. wc), but must be
no less than 0.16 psig (4.5-in. wc).
Fig. 12—Heating and Cooling Application Wiring Diagram
A95241
115-VOLT FIELD-
SUPPLIED
FUSED
DISCONNECT
AUXILIARY
J-BOX
CONTROL
BOX
24-VOLT
TERMINAL
BLOCK
THREE-WIRE
HEATING-
ONLY
FIVE
WIRE
NOTE 1
NOTE 2
FIELD-SUPPLIED
FUSED DISCONNECT
CONDENSING
UNIT
TWO
WIRE
FURNACE
R
G
C
W
C
R
G
Y
GND
GND
FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING
208/230- OR
460-VOLT
THREE
PHASE
208/230-
VOLT
SINGLE
PHASE
WHT
BLK
WHT
BLK
NOTES:
Connect Y-terminal as shown for proper operation.
Some thermostats require a "C" terminal connection as shown.
If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.
W
Y
GND
THERMOSTAT
TERMINALS
1.
2.
3.
Fig. 11—Control Board
A95086
C
OM
24V
HUM
G
R
Y
W
3-AMP FUSE
HUMIDIFIER TERMINAL
(24-VAC 0.5 AMP MAX)
LED OPERATION &
DIAGNOSTIC LIGHT
HARNESS CONNECTOR
24-V TRANSFORMER SEC-2
SPARE-1
SPARE-2
EAC-1
EAC-ELECTRONIC AIR CLEANER
TERMINALS (115-VAC 1.5 AMP MAX)
EAC-2
115-VAC (L2) NEUTRAL
CONNECTION
24-V THERMOSTAT
TERMINALS
BLOWER SPEED
SELECTION TERMINALS
INDUCER MOTOR
CONNECTOR
115-VAC (L1)
POWER SUPPLY
HOT SURFACE
IGNITOR CONNECTOR
HEAT
COOL
SEC-1
TEST/TWIN
9
