GM9S80 Service Manual

SYSTEM OPERATION
9
3. When the center switch is pressed, the current dis-
played speed will be selected, and control will imme-
diately apply that speed setting.
THERMOSTAT
CALL
AVAILABLE
SPEEDS
G
F01
F02
F03
(DEFAULT)
F04
F05
F06
F07
F08
F09



On a call for low stage cooling, the Y/Y1 or Y/Y1 and G ther-
mostat contacts close signaling the furnace control board
with 24 VAC on Y/Y1 or Y/Y1 and G terminals.
The 7-Segment will display the cool mode:1 A C
The compressor and condenser fan are energized.
The circulator fan is energized at low cool speed after
a cool on delay. The electronic air cleaner will also be
energized.

      󰀨  
begins.
󰀨
circulator and air cleaner relay are de-energized.

On a call for 2nd stage cooling, the Y2 or Y2 and G thermo-
stat contacts close signaling the furnace control board with
24 VAC on Y2 or Y2 and G terminals.
The 7-Segment will display the cool mode: 2 A C
The compressor and condenser fan are energized.
The circulator fan is energized at cool speed after a
cool on delay. The electronic air cleaner will also be
energized.

      󰀨  
begins.
󰀨
circulator and air cleaner relay are de-energized

To change the main blower speed in COOLING mode, fol-
low the following steps:
1. 

COOLING). Press the center switch and LED will dis-
      
speed number from 1 to 9).
2. The control will rotate available speed number every
time left/right switches are pressed. All 9 speeds are
available for both Single and Two Stage cooling.
3. When the center switch is pressed, the current dis-
played speed will be selected, and control will apply

THERMOSTATCALL AVAILABLESPEEDS
Y/Y1
F01
F02
F03
F04(DEFAULT)
F05
F06
F07
F08
F09


THERMOSTATCALL AVAILABLESPEEDS
Y2
F01
F02
F03
F04
F05(DEFAULT)
F06
F07
F08
F09


1. Set the thermostat to the lowest setting. The inte-


󰀨

2. Remove the burner compartment door and move the
furnace gas valve manual control to the OFF position.
3.   󰀨  
furnace.
4. Replace the burner compartment door.