Filter
Top Products
a. Draft safeguard switch.
b. Inducer motor.
c. Pressure switch(es).
d. Limit overtemperature switch(es).
e. Gas valve.
f. Hot surface ignitor.
g. Flame-sensing electrode.
h. Wiring connectors leading to control.
4. Remove 2 screws that secure relief box. (See Fig. 4.)
5. Remove 8 screws that secure flue collector box to center
panel. Be careful not to damage sealant.
6. Remove complete inducer assembly from furnace, exposing
flue openings.
7. Using field-provided small wire brush, steel spring cable,
reversible electric drill, and vacuum cleaner, clean cells as
follows:
a. Assemble wire brush and steel spring cable.
(1.) Use 48 in. of 1/4-in. diameter high-grade steel
spring cable (commonly known as drain clean-out
or Roto-Rooter cable).
(2.) Use 1/4-in. diameter wire brush (commonly known
as 25-caliber rifle cleaning brush).
NOTE: The materials needed in items (1.) and (2.) can usually be
purchased at local hardware stores.
(3.) Insert twisted wire end of brush into end of spring
cable, and crimp tight with crimping tool or strike
with ball-peen hammer. TIGHTNESS IS VERY
IMPORTANT.
(4.) Remove metal screw fitting from wire brush to
allow insertion into cable.
b. Clean each heat exchanger cell.
(1.) Attach variable-speed, reversible drill to end of
spring cable (end opposite brush).
(2.) Remove cell outlet plates. IMPORTANT: Replace
screws in center panel to secure heat exchanger
cells before cleaning.
(3.) Insert brush end of cable into upper opening of cell
and slowly rotate with drill. DO NOT force cable.
Gradually insert at least 36 in. of cable into 2 upper
passes of cell. (See Fig. 5.)
(4.) Work cable in and out of cell 3 or 4 times to obtain
sufficient cleaning. DO NOT pull cable with great
force. Reverse drill and gradually work cable out.
(5.) Remove burner assembly and cell inlet plates.
NOTE: Be very careful when removing the burner assembly to
avoid breaking the ignitor. See Fig. 6 for the correct ignitor
location.
(6.) IMPORTANT: Replace screws in center panel to
secure heat exchanger cells before cleaning.
(7.) Insert brush end of cable in lower opening of cell,
and proceed to clean 2 lower passes of cell in same
manner as 2 upper passes.
(8.) Repeat foregoing procedures until each cell in
furnace has been cleaned.
(9.) Using vacuum cleaner, remove residue from each
cell.
(10.) Using vacuum cleaner with soft brush attachment,
clean burner assembly.
(11.) Reinstall cell outlet plates and screws FIRST;
then, reinstall cell inlet plates and burner assem-
bly. Care must be exercised to center the burners
in the cell openings.
8. After cleaning flue openings, clean flue collector. Check
sealant on flue collector to ensure that it has not been
damaged. If new sealant is needed, contact your dealer or
distributor.
9. Replace flue collector assembly, making sure all 8 screws
are secure.
10. Reinstall relief box.
11. 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.
Fig. 5—Cleaning Heat Exchanger Cell
A91252
Fig. 6—Position of Ignitor to Burner
A93347
BURNER
IGNITOR
11
32
"
7
8
"
C
L
C
L
IGNITOR
ASSEMBLY
CELL
PANEL
BURNER
13
32
"
HOT
SURFACE
IGNITOR
ASSEMBLY
—4—