Cleaning Heat Exchanger - International comfort products R80ESN Installation Instructions Manual

c. Perform component self- -test as shown at the bottom of
the SERVICE label, located on the front of blower access
door.
d. Verify blower is rotating in the correct direction.
17. If furnace is operating properly, RELEASE BLOWER
ACCESS DOOR SWITCH. Remove any jumpers or re-
connect any disconnected thermostat leads. Replace blow-
er access door.
18. Downflow or horizontal furnaces with vent pipe through
furnace only:
a. Install and connect short piece of vent pipe inside furnace
to existing vent.
b. Connect vent connector to vent elbow.
19. Reinstall outer door.
20. Cycle furnace through one complete heating and cooling
cycle. Verify the furnace temperature rise as shown in
"Adjustments" Section. Adjust temperature rise as shown
in "Adjustments" Section. If outdoor temperature is below
70_F, (21_C) turn off circuit breaker to outdoor unit be-
fore running furnace in the cooling cycle. Turn outdoor
circuit breaker on after completing cooling cycle.

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 adjustment 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:
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 discon-
necting wires from switches because damage may occur):
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.
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. Remove NOx baf-
fles if installed.
NOTE: Be very careful when removing burner assembly to
avoid breaking igniter. See Fig. 45 and 46 for correct igniter
location.
441 01 6200 00
9. Using field- -provided 25- -caliber rifle cleaning brush,
36- -in. (914 mm) long, 1/4" (6 mm) diameter steel spring
cable, a variable speed, reversible electric drill, and vacu-
um cleaner, clean cells as follows:
a. Remove metal screw fitting from wire brush to allow in-
b. Insert the twisted wire end of brush into end of spring ca-
NOTE: The materials needed in item 9 can usually be purchased
at local hardware stores.
Specifications are subject to change without notice.
sertion into cable.
ble, and crimp tight with crimping tool or crimp by strik-
ing with ball- -peen hammer. TIGHTNESS IS VERY IM-
PORTANT.
9/32"
7.1mm
Fig. 45 - - Igniter Position- -Side View
Fig. 46 - - Igniter Position- -Top View
(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 ca-
ble. Gradually insert cable into upper pass of cell.
(See Fig. 47 .)
(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.
5/16"
7.9mm
A05025
1-7/8
47.6 mm
A05026
43