19
checks.
• Induced draft blower is energized for 15 second pre-
purge period causing pressure switch contacts to
close.
• Igniter warm up begins after 15 second prepurge
expires.
• Gas valves open 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 heating speed follow-
ing a fixed thirty second blower on delay. Electronic air
cleaner terminals are energized with circulator blower.
• Furnace operates; 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.
• The circulator blower remains on heating speed for the
selected heat off delay period.
• Furnace awaits the next call from thermostat.
Cooling Mode
The normal operational sequence in cooling mode is as
follows:
• R and Y 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 cool speed following
a fixed five second on delay. Electronic air cleaner
terminals are energized with circulator blower.
• Furnace circulator blower and outdoor cooling unit
run, integrated control module monitors safety circuits
continuously.
• R and Y thermostat contacts open, completing the call
for cool.
• Outdoor fan and compressor are de-energized.
•
Circulator blower is de-energized following a fixed forty
five second cool off delay period. Electronic air cleaner
terminals are de-energized.
• Furnace awaits the next call from thermostat.
Fan Only Mode
The normal operational sequence in fan only mode is as
follows:
• R and G thermostat contacts close, initiating a call for
fan.
• Integrated control module performs safety circuit
checks.
• Circulator blower is energized on T1 speed. Electronic
air cleaner terminals are energized.
• Circulator blower runs, integrated control module mon-
itors safety circuits continuously.
• R and G thermostat contacts open, completing the call
for fan.
• Circulator blower is de-energized. Electronic air clean-
er terminals are de-energized.
• Furnace awaits the next call from thermostat.
START-UP PROCEDURE AND ADJUSTMENT
Furnace must have a 115 VAC power supply properly con-
nected and grounded. Proper polarity must be maintained for
correct operation. An interlock switch prevents furnace oper-
ation if the blower door is not in place. Keep the blower access
door in place except for inspection and maintenance.
This furnace is also equipped with a self-diagnosing electronic
control module. In the event a furnace component is not oper-
ating properly, the control module LED will flash on and off in
a factory-programmed sequence, depending on the problem
encountered. This light can be viewed through the observation
window in the blower access door. Refer to the
Troubleshoot
-
ing Chart
for further explanation of the fault codes.
Furnace operation
Purge gas lines of air prior to start-up. Do not purge lines into
an enclosed burner compartment.
Check for leaks using an approved chloride-free soap and
water solution, an electronic combustible gas detector, or
other approved method. Verify that all required kits (propane
gas, high altitude, etc.) have been appropriately installed.
NOTE: An interlock switch prevents furnace oper-
ation if the blower door is not in place. Keep the
blower access doors in place except for inspec
-
tion and maintenance.
Furnace Start-up
1.
Close the manual gas shutoff valve external to the
furnace.
2.
Turn off the electrical power to the furnace.
3. Set the room thermostat to the lowest possible setting.
4. Remove the burner compartment door.
NOTE: This furnace is equipped with an ignition de
-
vice which automatically lights the burner. Do not
try to light the burner by hand.
5. White-Rodgers valves
Push the switch to the OFF
position.
6.
Wait five minutes then smell for gas. Be sure to check
near the floor, as some types of gas are heavier than
air.
7.
If gas can be smelled following the five minute waiting
peri od in Step 6, immediately follow the instructions
on Page 3 of this manual. If you do not smell gas after
five minutes:
White-Rodgers valves:
Push the switch to the ON
