Filter
Top Products
8. Clean cells using field-provided small wire brush, steel spring
cable, reversible electric drill, and vacuum cleaner.
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 steel 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 steel
spring cable (end opposite brush).
(2.) 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. 8.)
(3.) 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.
(4.) Remove burner assembly and cell inlet plates.
Be very careful when removing the burner assembly to avoid
breaking the ignitor. See Fig. 9 for the correct ignitor location.
(5.) Replace screws in center panel and cells before
cleaning.
(6.) 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.
(7.) Repeat foregoing procedures until each cell in furnace
has been cleaned.
(8.) Remove residue from each cell using vacuum cleaner.
(9.) Clean burner assembly using vacuum cleaner with soft
brush attachment.
(10.) Reinstall cell inlet plates and burner assembly. Care
must be exercised to center the burners in the cell
openings.
9. After cleaning flue openings, check sealant on flue collector to
ensure that it has not been damaged. If new sealant is needed,
contact your dealer or distributor.
10. Clean and replace flue collector assembly, making sure all 8
screws are secure.
11. Reinstall relief box.
12. Reconnect wires to the following components.
a. Draft safeguard switch
b. Inducer motor
c. Pressure switch
d. Limit overtemperature switch(es)
e. Gas valve
f. Hot surface ignitor
g. Flame-sensing electrode
h. Two wiring connectors leading to control
13. Reconnect vent pipe to relief box. Replace vent pipe enclosure
(downflow/horizontal furnace only).
14. Replace blower access door only.
15. Turn on electrical power and gas.
16. Set thermostat and check furnace for proper operation.
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.
17. Check for gas leaks.
18. Replace control access door on upflow furnace.
19. On downflow/horizontal furnaces, remove blower access
door, replace control access door first, then replace blower
access door and secure with 2 screws in front of door.
Fig. 8—Cleaning Heat Exchanger Cell
A91252
Fig. 9—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
5