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CUT HAZARD
Failure to follow this caution may result in minor personal
injury.
Use care when cutting support rods in filters to protect against
flying pieces and sharp rod ends. Wear safety glasses, gloves,
and appropriate protective clothing.
UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent unit
operation.
For airflow requirements above 1800 CFM, see Air Delivery
table in Product Data literature for specific use of single side
inlets. The use of both side inlets, a combination of 1 side and
the bottom, or the bottom only will ensure adequate return air
openings for airflow requirements above 1800 CFM.
NOTE:
Side return-air openings can ONLY be used in UPFLOW
configurations. Install filter(s) as shown in Fig. 26.
Bottom return-air opening may be used with all 4 orientations.
Filter may need to be cut to fit some furnace widths. Install filter
as shown in Fig. 27.
NOTE:
Remove and discard bottom closure panel when bottom
inlet is used.
Step 6—Bottom Closure Panel
These furnaces are shipped with bottom enclosure panel installed
in bottom return-air opening. This panel MUST be in place when
side return air is used.
To remove bottom closure panel, perform following:
1. Tilt or raise furnace and remove 2 screws holding front filler
panel. (See Fig. 28.)
2. Rotate front filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall front filler panel and screws.
Step 7—Gas Piping
Gas piping must be installed in accordance with national and local
codes. Refer to current edition of NFGC in the United States.
Canadian installations must be made in accordance with NSCNG-
PIC and all authorities having jurisdiction.
Gas supply line should be a separate line running directly from
meter to furnace, if possible. Refer to Table 5 for recommended
gas pipe sizing. Risers must be used to connect to furnace and to
meter. Support all gas piping with appropriate straps, hangers, etc.
Use a minimum of 1 hanger every 6 ft. Joint compound (pipe dope)
should be applied sparingly and only to male threads of joints. Pipe
dope must be resistant to propane gas.
Fig. 26—Filter Installed for Side Inlet
A93045
FILTER
RETAINER
WASHABLE
FILTER
Fig. 27—Bottom Filter Arrangement
A00290
WASHABLE
FILTER
FILTER
SUPPORT
FILTER
RETAINER
17
1
⁄
2
-IN. WIDE
CASINGS ONLY:
INSTALL FIELD-SUPPLIED
FILTER FILLER STRIP
UNDER FILTER.
1
″
24
1
/
2
″
3
″
21-IN. WIDE
CASINGS ONLY:
SUPPORT RODS (3)
EXTEND 1/4" ON EACH
SIDE OF FILTER AND
REST ON CASING FLANGE
Fig. 28—Removing Bottom Closure Panel
A93047
BOTTOM
CLOSURE
PANEL
FRONT FILLER
PANEL
23
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