International comfort products F9MXT0401410A Service And Technical Support Manual page 28

SERVICE AND TECHNICAL SUPPORT MANUAL
the prepurge period, then shut off for 24 seconds then
come back on at LO HEAT speed. When the W/W1 input
signal disappears, the furnace control begins a normal
inducer post−purge period and the blower remains
running at LO HEAT
W/W1−and−Y1−and−G signals disappear at the same
time, the blower motor BLWM will remain on for the
selected heat−off
R−to−W/W1−and−Y1 signals disappear, leaving the G
signal, the blower motor BLWM will remain on for the
selected heat−off delay
continuous−blower speed.
When the R−to−W/W1−and−Y/Y2, R−to−W/W1−and−
Y/Y2− and−G, R−to−W/W1−and−Y1−and−Y/Y2,
R−to−W/W1−and− Y1−and−Y/Y2−and−G circuits are
energized the furnace control CPU will switch to or turn
on the blower motor BLWM at COOL speed, and begin a
high−heat cycle. The blower motor BLWM will remain on
until the end of the prepurge period, then shut off for 24
seconds then come back on at HI HEAT speed. When
the W/W1 input signal disappears, the furnace control
begins a normal inducer post−purge period and the
blower switches to COOL speed after a 3 second delay.
If the R−to−W/W1−and−Y/Y2−and−G
R−to−W/W1−and−Y1−and−
disappear at the same time, the blower motor BLWM will
remain on for the selected heat−off delay period. If the
R−to−W/W1−and−Y/Y2
and−Y1−and−Y/Y2 signals disappear, leaving the G
signal, the blower motor BLWM will remain on for the
selected heat−off delay
continuous−blower speed.
Component Self Test
Refer to page 14 for instructions.
Two−Stage Furnace with Single−Speed
Figure 17
Air Conditioner
NOTE 9
28
speed. If the R−to−
delay period. If the
period then switch
or
or
Y/Y2−and−G signals
or R−to−W/W1−
period then switch
Specifications subject to change without notice.
Two−Stage Furnace with Two−Stage Air
Figure 18
Conditioner
NOTE 9
to
to
Two−Stage Furnace with Single−Stage
Figure 19
Heat Pump (Dual Fuel)
NOTE 9
Gas Furnace: (F/G)9MXT
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