37
B
LOWER
H
EAT
O
FF
D
ELAY
T
IMINGS
The integrated control module on 96% models provides a selectable heat off delay function. The heat off delay period may be set to
100 or 150 seconds by cutting the jumper on the control module. The delay is factory shipped at 150 seconds but may be changed
to suit the installation requirements and/or homeowner preference.
The integrated control board on 92% models has a fixed blower off delay of 150 seconds.
N
ORMAL
S
EQUENCE
OF
O
PERATION
P
OWER
U
P
The normal power up sequence is as follows:
•
115 VAC power applied to furnace.
•
Integrated control module performs internal checks.
•
LED will flash once at power up then remain on.
•
Integrated control module monitors safety circuits continuously.
•
Furnace awaits call from thermostat.
H
EATING
M
ODE
The normal operational sequence in heating mode is as follows:
•
R and W thermostat contacts close, initiating a call for heat.
•
Integrated control module performs safety circuit checks.
•
Induced draft blower is energized for a 15-second prepurge.
•
Pressure switch contacts are closed.
•
96% models 115 VAC HUM terminal is energized.
•
Igniter warm up begins upon presence of closed pressure switch contacts.
•
Gas valve opens at end of igniter warm up period, delivering gas to burners and establishing flame.
•
Integrated control module monitors flame presence. Gas valve will remain open only if flame is detected.
•
Circulator blower is energized on heat speed following a thirty (30) second blower on delay.
•
96% models 115 VAC EAC terminal is energized.
•
Furnace runs, integrated control module monitors safety circuits continuously.
•
R and W thermostat contacts open, completing the call for heat.
•
Gas valve closes, extinguishing flame.
•
Induced draft blower is de-energized following a fifteen second post purge.
•
96% models HUM terminal is de-energized.
•
For 96% Models:
Circulator blower continues running for the selected heat off delay period Factory set at 150
seconds.
•
EAC terminal is de-energized
For 92% Models:
The blower off delay is 150 seconds (non-adjustable).
•
Furnace awaits next call from thermostat.
C
OOLING
M
ODE
The normal operational sequence in cooling mode is as follows:
•
R,Y, G thermostat thermostat contacts close, initiating a call for cool.
•
Integrated control module performs safety circuit checks.
•
Outdoor fan and compressor are energized.
•
Circulator blower is energized on the cool speed.
•
96% models 115 VAC EAC terminal is energized.
•
Furnace circulator blower and outdoor cooling unit run their appropriate speeds, integrated control module monitors
safety circuits continuously.
•
R,Y, G thermostat contacts open, completing the call for cool.
•
Outdoor fan and compressor are de-energized.
•
Circulator blower continues running during a cool off delay period of 45 seconds.
•
Furnace awaits next call from thermostat.
