14
18-CD37D1-2-EN
Installer’s Guide
INSTALLING THE FILTER
The filter may need to be cut to fit the unit depending on the
location of the return air filter.
A score line and the words “CUT HERE” are located on the
end of the filter. If your application requires cutting the filter, do
so as indicted by the score mark.
TYPICAL DOWNFLOW FURNACE
RETURN AIR FILTER INSTALLATIONS
Two filters are factory supplied for each downflow furnace.
These furnaces require high velocity type air filters. Downflow
furnace filters must be located outside the furnace cabinet.
Typical installations are shown in Figure 25. Table 8 provides
information for installation of the filter retaining brackets
shipped with downflow furnaces.
Table 7
MODELS
NUMBERS
CABINET
WIDTH
FILTER
QTY & SIZE
M952V060BD36A
M952V080BD36A
17-1/2"
2 - 14" X 20" X 1"
M952V100CD48A
21"
2 - 16" X 20" X 1"
M952V120DD60A
24-1/2"
2 - 16" X 20 X 1"
* Last letter may be "A" or "T"
Figure 24
Figure 25
UPFLOW FILTER CLIP / BRACKET INSTALLATION
1. Determine the location to be used. The furnace cabinet has
dimples for location of the furnace clips (
Side return only
). Pre-
drill clearance holes with a 3/16" drill. Bottom return holes are
pre-drilled.
2. Install the clips in front and rear of the desired location using
the screws provided. The filter clip with the leaf spring mounts
in the rear of the cabinet. See Figure 24.
SIDE
CUT
-OUT
ALTERNATE SIDE
FILTER CLIPS
LOCATIONS
ALTERNATE BOTTOM
FILTER CLIPS LOCATIONS
Table 6
UNIT SIZE
RETURN AIR
BOTTOM
SIDE
17-1/2"
DO NOT CUT DO NOT CUT
21"
DO NOT CUT CUT ON LINE
24-1/2"
DO NOT CUT CUT ON LINE
Important: When using the supplied high velocity filters,
the filter support base must be installed into the furnace
duct flange prior to ductwork installation.
Remove the brackets from the blower compartment. They are
wrapped in foam and taped to the side of the downflow unit.
Remove the four screws securing the top panel. Save screws.
Slide the top panel forward approximately 1”.
With support tabs facing up, install the filter base by inserting one
end tab into the duct flange at the rear of the furnace.
Slide the top panel back to its original position, engaging the other
end tab in the slot. Replace screws.
Remove
brackets
Screw
locations
Flanges
upward
Airflo
w
DOWNFLOW/
HORIZONTAL
DOWNFLOW
Airflow
