Instruction manual

(8.) Using vacuum cleaner with soft brush attachment,
clean burner assembly.
(9.) Reinstall cell outlet plates and screws FIRST; then,
reinstall cell inlet plates and burner assembly. Care
must be exercised to center burners in cell openings.
12. Remove old sealant from center panel and collector box
flange and apply new sealant to collector box flange and
reinstall on center panel, making sure all screws are secure.
NOTE: A releasing agent such as PAM cooking spray or equiva-
lent (must not contain corn or canola oil, aromatic or halogenated
hydrocarbons or inadequate seal may occur) and RTV sealant
(G.E. 162, 6702, or Dow-Corning 738) are needed before starting
installation. DO NOT substitute any other type of RTV sealant.
G.E. 162 (P771-9003) is available through RCD in 3-oz tubes.
13. Reinstall relief box and inducer assembly.
NOTE: If inducer assembly gasket is damaged, use RTV sealant
to seal inducer assembly to collector box.
NOTE: A releasing agent such as PAM cooking spray or equiva-
lent (must not contain corn or canola oil, aromatic or halogenated
hydrocarbons or inadequate seal may occur) and RTV sealant
(G.E. 162, 6702, or Dow-Corning 738) are needed before starting
installation. DO NOT substitute any other type of RTV sealant.
G.E. 162 (P771-9003) is available through RCD in 3-oz tubes.
14. Reconnect wires to the following components:
a. Draft safeguard switch.
b. Inducer motor.
c. Pressure switches.
d. Limit overtemperature switch(es).
e. Gas valve.
f. Hot surface ignitor.
g. Flame-sensing electrode.
15. Reinstall internal vent pipe and enclosure on
downflow/horizontal furnaces only by reversing items 4a
through 4c.
NOTE: A releasing agent such as PAM cooking spray or equiva-
lent (must not contain corn or canola oil, aromatic or halogenated
hydrocarbons or inadequate seal may occur) and RTV sealant
(G.E. 162, 6702, or Dow-Corning 738) are needed before starting
installation. DO NOT substitute any other type of RTV sealant.
G.E. 162 (P771-9003) is available through RCD in 3-oz tubes.
16. Reinstall vent connector to furnace flue collar. After fully
assembling vent connector to furnace flue collar, securely
fasten vent connector to flue collar with 2 field-supplied,
corrosion-resistant, sheet metal screws located 180 degrees
apart and midway up the collar.
17. Replace blower access door only.
18. Turn power and gas to ON.
19. Set thermostat and check furnace for proper operation.
20. Verify blower airflow and speed changes between heating
and cooling.
21. Check for gas leaks.
22. Replace control door.
WARNING: Never use a match or other open flame to
check for gas leaks. Use a soap-and-water solution. A
failure to follow this warning could result in fire, personal
injury, or death.
IV. ELECTRICAL CONTROLS AND WIRING
NOTE: There may be more than 1 electrical supply to unit.
The electrical ground and polarity for 115-v wiring must be
maintained properly. Refer to Fig. 10 and 11 for field wiring
information and to Fig. 12 for unit wiring information. If the
polarity is NOT correct, the furnace control will display code 02 on
the status LED and prevent heat operation. The control system also
requires an earth ground for proper operation of the microproces-
sor.
With power disconnected to unit, check all electrical connections
for tightness. Tighten all screws on electrical connections. If any
smoky or burned connections are noticed, disassemble the connec-
tion, clean all parts and stripped wire, and reassemble properly and
securely. Electrical controls are difficult to check without proper
instrumentation; therefore, reconnect electrical power to unit and
observe unit through 1 complete operating cycle.
The 24-v circuit contains an automotive-type, 3-amp fuse located
on the main control. Any 24-v electrical shorts during installation,
service, or maintenance could cause this fuse to blow. If fuse
replacement is required, use ONLY a 3-amp fuse. The control will
display code 24 when fuse needs replacement.
The control in this furnace is equipped with an LED status light to
aid in installation, servicing, and troubleshooting. It can be viewed
through the sight glass or window on blower access door. The
control indicates status with the LED on continuously, rapid
flashing, or a code composed of 2 digits. (The first digit is the
number of short flashes, the second is the number of longs flashes.)
Refer to the service label on blower compartment door for code
explanations and useful troubleshooting suggestions. (See Fig. 13.)
It is important to note that power to furnace must not be interrupted
and furnace blower door must not be removed until the LED status
code(es) is recorded. When power to control is interrupted, status
memory is erased.
The control will store up to 5 previous codes but will not store
non-current code longer than 48 hr. To retrieve previous codes, if
present, no thermostat inputs to control must be present and all
time delays must expire. Remove 1 of the red main limit wires 1
to 4 sec until the LED light goes out, then reconnect it. (See Figs.
6 and 7.) (Do not leave red wire disconnected for longer periods of
time as control will assume an overtemperature condition exists
and will respond with indoor blower operation.) This places
control in status recall mode and displays first code stored in
memory. Record code and repeat the disconnect and reconnect of
red wire, recording each code until code 11 is displayed indicating
no additional faults. After last code is displayed or after 2 minutes
in the code recall mode, the control will return to normal standby
mode.
Use any recorded fault codes, service label, and troubleshooting
diagram to diagnose and correct any problem condition.
Fig. 9—Cleaning Heat Exchanger Cell
A91252
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