9
“X”
FLOOR OPENING
FLOOR
CAVITY
SUPPLY AIR DUCT
Figure 7. Floor Cavity
Figure 6. Cut-Out Dimensions for Downfl ow
Furnaces
FLOOR CUT-OUT
14 1/2” X 14 1/2”
FOR DOWNFLOW
FURNACES WITH
STD. DUCT
CONNECTORS
23 3/4"
17"
2 3/8" MIN.
OPTIONAL
REFRIGERANT LINE
4 1/4” X 3 3/4”
REAR WALL OF CLOSET OR ALCOVE
3/4"
FURNACE OUTLINE
FURNACE
DOOR
5”
C
L
OPTIONAL SUPPLY
WIRE ENTRANCE
3” X 6 1/4”
20"
3 3/8”
16 5/8"
10"
23 3/4"
17"
2 3/8"
MIN.
OPTIONAL
REFRIGERANT LINE
4 1/4” X 3 3/4”
REAR WALL OF CLOSET OR ALCOVE
3/4"
FURNACE OUTLINE
FURNACE
DOOR
5”
OPTIONAL SUPPLY
WIRE ENTRANCE
3” X 6 1/4”
20"
3 3/8”
16 5/8"
10"
FLOOR CUT-OUT
14 1/4” DIAMETER
FOR DOWNFLOW
FURNACES WITH
ROUND DUCT
CONNECTORS
C
L
STANDARD DUCT CONNECTOR
ROUND DUCT CONNECTOR
Figure 5. Cut-Out Dimensions for Upfl ow
Furnaces
FLOOR CUT-OUT
17 1/2” X 14”
FOR UPFLOW
FURNACES WITH
STD. DUCT
CONNECTORS
23 3/4"
OPTIONAL
REFRIGERANT LINE
3 1/8” X 5 3/4”
REAR WALL OF CLOSET OR ALCOVE
3/4"
FURNACE OUTLINE
FURNACE
DOOR
3”
C
L
20"
10"
18 5/8"
1 3/4" MIN.
23 3/4"
OPTIONAL
REFRIGERANT LINE
3 1/8” X 5 3/4”
REAR WALL OF CLOSET OR ALCOVE
3/4"
FURNACE OUTLINE
FURNACE
DOOR
3”
20"
10"
18 5/8"
1 3/4"
MIN.
FLOOR CUT-OUT
14 1/4” DIAMETER
FOR UPFLOW
FURNACES WITH
ROUND DUCT
CONNECTORS
C
L
STANDARD DUCT CONNECTOR
ROUND DUCT CONNECTOR
Locating & Cutting Floor Openings
Floor cut-outs must be carefully located to avoid
misalignment of the furnace and air duct. Standard and
round cutouts for upfl ow furnaces are shown in Figure
5. Figure 6 displays the cutouts for downfl ow furnaces.
1. Measure and mark the centerline of the cutout. Provide
minimum clearances at rear and right side walls of
closet or alcove for installation of furnace and wiring.
2. Using the centerline as a starting point, draw the rest
of the duct cut-out to the dimensions shown in Figures
5 or 6.
NOTE:
Additional provisions may be necessary
for optional air conditioning or heat pump if refrigerant
lines are installed elsewhere than at the front of the
furnace. The refrigerant and entrance supply opening
dimensions may be adjusted ± 1/2”.
3. Cut out the fl oor opening 1/16” larger than the actual
cutout drawn. This will allow some clearance when
installing the duct connector.
4. Measure from the top of the fl oor down to the top of the
supply air duct to obtain the depth of the fl oor cavity.
NOTE:
The depth of the fl oor cavity shown as “X” in
Figure 7 will determine the correct duct connector.
5. Determine which duct connector to use from Table 2
(page 10).
