GMES8 GCES8 Installation Instructions

23
HEATING M ODE
(M ODE DIP SW ITCH IS SET TO “1 STG” POSITION)
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 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 high heat speed following
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 high speed for the
selected heat off delay period.
• Furnace awaits the next call from thermostat.
COOLING M ODE
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 M ODE
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 low heat speed.
Electronic air cleaner terminals are energized.
• Circulator blower runs, integrated control module
monitors safety circuits continuously.
• R and G thermostat contacts open, completing the call for
fan.
• Circulator blower is de-energized. Electronic air cleaner
terminals are de-energized.
• Furnace awaits the next call from thermostat.
S TART - UP P ROCEDURE A ND A DJUSTM ENT
Furnace must have a 115 VAC power supply properly connected
and grounded. Proper polarity must be maintained for correct
operation. An interlock switch prevents furnace operation 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 operating
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 Troubleshooting Chart for fur-
ther 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 operation if the blower
door is not in place. Keep the blower access doors in place except
for inspection 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 device 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.
Honeywell valves: Slide 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
period 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 position.
Honeywell valves: Slide the switch to the ON position.