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Condensate Hose Screen (FIGURE 58)
Check the condensate hose screen for blockage and
clean if necessary.
1 - Turn off power to the unit.
2 - Remove hose from cold end header box. Twist and
pull screen to remove.
3 - Inspect screen and rinse with tap water if needed.
4 - Reinstall screen and turn on power to unit.
Condensate Hose Screen
Hose
FIGURE 58
Cleaning Heat Exchanger
If cleaning the heat exchanger becomes necessary, follow
the below procedures and refer to figure 1 when disas
-
sembling unit. Use papers or protective covering in front of
furnace while removing heat exchanger assembly.
1 - Turn off electrical and gas supplies to the furnace.
2 - Remove the furnace access panels.
3 - Disconnect the wires from the gas valve.
4 - Remove gas supply line connected to gas valve.
Remove the burner box cover (if equipped) and
remove gas valve/manifold assembly.
5 - Remove sensor wire from sensor. Disconnect 2-pin
plug from the ignitor.
6 - Disconnect wires from flame roll-out switches.
7 - Loosen clamps at vent elbow. Disconnect condensate
drain tubing from flue collar. and remove the vent
elbow.
8 - Loosen clamps and remove combustion air intake
flexible connector if equipped.
9 - Remove four burner box screws at the vestibule panel
and remove burner box. Set burner box assembly
aside.
NOTE -
If necessary, clean burners at this time.
Follow procedures outlined in Burner Cleaning
section.
10 - Mark and disconnect all combustion air pressure
tubing from cold end header collector box.
11 - Mark and remove wires from pressure switch
assembly. Remove pressure switch assembly.
Keep tubing attached to pressure switch assembly.
.
12 - Disconnect the plug from the combustion air inducer.
Remove two screws which secure combustion air
inducer to collector box. Remove combustion air
inducer assembly. Remove ground wire from vest
panel.
13 - Remove electrical junction box from the side of the
furnace.
14 - Disconnect condensate line from cold end header
box. Remove cold end header box.
15 - Loosen clamps on exhaust and air intake pipe seal
plate. Slide exhaust and intake pipes up and out to
clear blower deck. Remove exhaust and air intake
pipe seal plate.
16 - Mark and disconnect any remaining wiring to heating
compartment components. Disengage strain relief
bushing and pull wiring and bushing through the
hole in the blower deck.
17 - Remove the primary limit from the vestibule panel.
18 - Remove two screws from the front cabinet flange
at the blower deck. Spread cabinet sides slightly to
allow clearance for removal of heat exchanger.
19 - Remove screws along vestibule sides which secure
vestibule panel and heat exchanger assembly to
cabinet. Remove two screws from blower rail which
secure top heat exchanger flange. Remove heat
exchanger from furnace cabinet.
20 - Back wash heat exchanger with soapy water
solution or steam. If steam is used it must be below
275°F (135°C) .
21 - Thoroughly rinse and drain the heat exchanger.
Soap solutions can be corrosive. Take care to rinse
entire assembly.
22 - Reinstall heat exchanger into cabinet making sure
that the clamshells of the heat exchanger assembly
are engaged properly into the support bracket on
the blower deck. Remove the indoor blower to view
this area through the blower opening.
23 - Re-secure the supporting screws along the vestibule
sides and top to the cabinet.
24 - Reinstall cabinet screws on front flange at blower
deck.
25 - Reinstall the primary limit on the vestibule panel.
26 - Route heating component wiring through hole in
blower deck and reinsert strain relief bushing.
27 - Reinstall electrical junction box.
