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G50DF(X) Internal Flue Pipe and Chase
FIGURE 25
Unit Top Cap
Internal Flue
Pipe
with Adaptor
Flue Chase
with Gaskets
Screw (1)
Internal
Flue Pipe
RTV
Silicone
Sealant
Combustion
Air Inducer
FIGURE 26
G50DF(X) CAI & Burner Box Removal
Burner Box Assembly
Heat Exchanger
Combustion
Air Inducer
8 −Remove the collector box located behind the combus-
tion air inducer. Be careful with the collector box gas-
ket. If the gasket is damaged, it must be replaced to
prevent leakage.
9 −Label the wires from gas valve and rollout switches,
then disconnect them.
10 −Disconnect gas supply piping. Remove four screws
securing the burner manifold assembly to the vestibule
panel and remove the assembly from the unit.
11 −
NO
x
units only
−
Remove the three screws that attach
the
NO
x
insert to the corbel at the entrance to each
heat exchanger section. Carefully remove the
NO
x
in-
sert from each section. See figure 27.
NO
x
INSERTS
(X models only)
FIGURE 27
NOx INSERT
12 −Insert the brush end of cable snake into the top of one
of the heat exchanger openings.
Do not force the
cable into the heat exchanger.
Insert the cable and
operate the drill on slow speed. Move the cable in and
out of the heat exchanger section three or four times or
until sufficient cleaning is accomplished. Reverse drill
and slowly work the cable out of opening.
13 −Repeat procedure for each heat exchanger section.
14 −After each of the top heat exchanger sections has
been cleaned, insert the brush end of the cable snake
into the bottom openings of each of the heat exchanger
sections and clean as described in step 8.
15 −Remove the cable from the heat exchanger. Use a
vacuum cleaner to remove debris knocked loose dur-
ing cleaning.
16 −Attach the exhaust end (positive pressure) of the vacu-
um cleaner to the top of the heat exchanger section.
Any loose debris will be forced to the bottom of the heat
exchanger section. Vacuum debris from bottom open-
ings.
17 −Replace collector box and combustion air inducer.
Check gaskets for damage. Damaged gaskets must
be replaced to avoid heat exchanger leaks. Replace all
screws to the collector box and combustion air inducer.
Failure to replace all screws may cause leaks.
18 −To clean the burner, run a vacuum cleaner with a soft
brush attachment over the face of burners. Inspect in-
side the burners and crossovers for any blockage.
Clean the inside of the burner if necessary.
19 −
NO
x
Units −
Reattach the NO
x
inserts to the corbels at
the entrance to each heat exchanger opening. See fig-
ure 27.
20 −Reinstall the burner/manifold assembly on the vesti-
bule panel.
21 −Reconnect wires to pressure switch, roll−out switches,
gas valve and combustion air inducer. Refer to unit wir-
ing diagram.
22 −Use screws to resecure the junction box to the cabinet.
23 −Apply RTV/high temperature silicone sealant between
the internal flue pipe and the combustion air inducer.
