Maytag Goodman GM9C96 Service And Troubleshooting page 15

SYSTEM OPERATION
• The 2nd stage gas heat speed of the indoor blower is
energized
• When the thermostat is satisfied:
• The gas valve is de-energized.
• The inducer remains energized for the post purge period
(15 seconds).
• The indoor blower runs for the selected off delay period
(90 seconds by default, adjustable from 30 – 180
seconds).
Call for 2nd Stage Heat During 1st Stage Heat Operation
• The control board receives a 24 VAC signal on the W2
terminal.
• The inducer motor is enabled at high speed.
• Closure of the 2nd stage pressure switch will energize
the high fire stage of the gas valve.
• The 2nd stage gas heat speed of the indoor blower is
energized.
Heating Mode Speed Selection
To change the main blower speed in HEATING mode, follow
the following steps:
1. Press the left or right switch until LED displays "gA1" (for
single-stage HEATING) or "gA2" (for two-stage HEATING).
Press the center switch and LED will display the selected
speed number as Fxx (xx: Blower speed number).
2. The control will rotate available speed number every time
left / right switches are pressed. The table below shows
the available speeds for low & high heat mode.
3. Press the center switch to save the selection.
NOTE: Always refer to the Heating Chart to choose from
available heating speeds
THERMOSTAT CALL
W/W1
W2
One and Two-Stage Heating Speed Table for 2 Stage IFC
Continuous Fan Mode Speed Selection
To change the main blower speed in circulation mode, follow
the following steps:
1. Press the left or right switch until LED displays "FSd".
Press the center switch and LED will display the selected
speed number as Fxx (xx: Blower speed number from 1
to 9). F03 is the default speed for circulation.
AVAILABLE SPEEDS
F01 (DEFAULT)
F03
F04
F02 (DEFAULT)
F04
F05
2. The control will rotate available speed number every time
left/right switches are pressed. All 9 speeds are available
for circulation.
3. When the center switch is pressed, the current displayed
speed will be selected, and control will immediately apply
that speed setting.
THERMOSTAT
CALL
G
Circulation Speed Table for 2 Stage IFC
Cooling Mode Sequence of Operation
Low Stage Cooling Mode Sequence:
On a call for low stage cooling, the Y/Y1 or Y/Y1 and G
thermostat 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.
• After the thermostat is satisfied, the compressor is de-
energized and the Cool Mode Fan Off Delay period begins.
• Following the Cool Mode Fan Off Delay period, the cool
circulator and air cleaner relay are de-energized.
2nd Stage Cooling Mode Sequence:
On a call for 2nd stage cooling, the Y2 or Y2 and G thermostat
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.
• After the thermostat is satisfied, the compressor is
de-energized and the Cool Mode Fan Off Delay period
begins.
• Following the Cool Mode Fan Off Delay period, the cool
circulator and air cleaner relay are de-energized
AVAILABLE
SPEEDS
F01
F02
F03 (DEFAULT)
F04
F05
F06
F07
F08
F09
15