Klimaire GM80S Series - Manual (Page 33)

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I&O manual
1. Turn OFF gas and electrical power to furnace.
2. Remove outer access door.
3. Disconnect vent connector from furnace vent elbow.
4. For downflow or horizontal furnace having an internal vent
pipe, remove internal vent pipe within the casing.
5. Disconnect wires to the following components. Mark wires to
aid in reconnection of (be careful when disconnecting wires
from switches because damage may occur):
a. Draft safeguard switch.
b. Inducer motor.
c. Pressure switch(es).
d. Limit overtemperature switch.
e. Gas valve.
f. Hot surface igniter.
g. Flame-sensing electrode.
h. Flame rollout switches.
6. Remove screws that fasten the collector box assembly to
the cell panel. Be careful not to damage the collector box.
Inducer assembly and elbow need not be removed from
collector box.
7. Disconnect gas line from gas manifold.
8. Remove the 5 screws that attach the burner assembly to
the cell panel. The gas valve and individual burners need
not be removed from support assembly.
(1.) Attach variable-speed, reversible drill to the end of
spring cable (end opposite brush).
(2.) Insert brush end of cable into the outlet opening of
cell and slowly rotate with drill. DO NOT force
cable. Gradually insert cable into upper pass of cell.
(See Fig. 34.)
(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.) Insert brush end of cable in burner inlet opening of
cell, and proceed to clean 2 lower passes of cell in
same manner as upper pass.
(5.) Repeat foregoing procedures until each cell in fur-
nace has been cleaned.
(6.) Using vacuum cleaner, remove residue from each cell.
(7.) Using vacuum cleaner with soft brush attachment,
clean burner assembly.
(8.) Clean flame sensor with fine steel wool.
(9.) Reinstall burner assembly. Center burners in cell
openings.
14.6 Cleaning Heat Exchanger
The following steps should be performed by a qualified service
agency:
NOTE: If the heat exchangers get a heavy accumulation of soot and
carbon, they should be replaced rather than trying to clean them
thoroughly. A heavy build-up of soot and carbon indicates that a
problem exists which needs to be corrected, such as improper adjust-
ment of manifold pressure, insufficient or poor quality combustion air,
incorrect size or damaged manifold orifice(s), improper gas, or a
restricted heat exchanger. Action must be taken to correct the
problem.
If it becomes necessary to clean the heat exchangers because of dust
or corrosion, proceed as follows:
NOTE: Be very careful when removing burner assembly to avoid
breaking igniter. See Fig. 32 and Fig.33 for correct igniter location.
9. Using field-provided 25-caliber rifle cleaning brush, 36-in.
(914 mm) long, 1/4" diameter steel spring cable, a variable
speed, reversible electric drill, and vacuum cleaner, clean
cells as follows:
a. Remove metal screw fitting from wire brush to allow in-
sertion into cable.
b. Insert the twisted wire end of brush into end of spring
cable, and crimp tight with crimping tool or crimp by
striking with ball-peen hammer. TIGHTNESS IS VERY
IMPORTANT.
Fig. 32 - Igniter Position-1
Fig. 33 - Igniter Position- 2
NOTE: The materials needed in item 9 can usually be purchased at
local hardware stores.
10. Remove old sealant from cell panel and collector box flange.
11. Spray releasing agent on the heat exchanger cell panel
where collector box assembly contacts cell panel.
NOTE: A releasing agent such as cooking spray or equivalent (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.
12. Apply new sealant to flange of collector box and attach to
cell panel using existing screws, making sure all screws
are secure.
13. Reconnect wires to the following components. (Use con-
nection diagram on wiring label, if wires were not marked
for reconnection locations.):
a. Draft safeguard switch.
b. Inducer motor.
c. Pressure switch(es).
d. Limit over-temperature switch.
e. Gas valve.
f. Hot surface igniter.
g. Flame-sensing electrode.
h. Flame rollout switches.
14. Reinstall internal vent pipe, if applicable.
Fig. 34 - Cleaning Heat Exchanger Cell
Flame sensor IgnIter
Furnace
right side
Furnace
Front