10
If Floor Cavity
“X” is:
Duct Connector
Type & Part Number
Standard Duct
Screw Down
7/8” / (22)
901987A
904008
2” / (51)
901988A
904009
4-1/4” / (108)
901989A
904010
6-1/4” / (159)
901990A
904011
8-1/4” / (210)
901991A
904012
10-1/4” / (260)
901992A
904013
12-1/4” / (311)
901993A
904014
NOTE:
Dimensions shown as Inches / (Millimeter)
Table 2. Duct Connector Sizes
Standard Duct Connector Installation
The standard duct connector is designed for use on ducts
12” in width.
NOTE:
Ducts narrower than 12” may not
allow suffi cient clearances for this type of installation. See
Narrow Duct Connector section.
1. Center the duct connector in the fl oor opening with
bottom tabs resting on top of the supply air duct.
2. Mark the cut-out area on the supply air duct by tracing
around the connector tabs (Figure 8) of the duct
connector.
3. Remove the duct connector and cut out the marked
area of the supply air duct 1/4” larger the actual cutout
drawn.
4. Install the duct connector back in the fl oor opening
with the bottom tabs extending into the supply air duct.
5. Install the mounting plate (Figure 8) under the back
side of the duct connector. Align the screw holes in
both components.
6. Secure the duct connector and the mounting plate to
the wood fl oor with appropriate size screws.
7. Bend the connector tabs on the bottom of the duct
connector upwards and as tight as possible against
the supply air duct.
Bend tabs
up 90°
Mounting Plate
Duct
Connector
Connector
Tabs
Supply
Air Duct
Wood Floor
Figure 8. Standard Duct Connector Installed
Figure 10. Narrow Air Duct Openings
OPTION 1
OPTION 2
Supply
Air Duct
F
old Flap Here
F
old Flap Here
Remove
this
Flap
Remove
this
Flap
Cut Here
Cut Here
Cut Here
Cut Here
Cut Here
Cut Here
Cut Here
Cut Here
Cut Here
F
old Flap Here
F
old Flap Here
DUCT CONNECTOR
SUPPLY
AIR DUCT
BEND TABS TIGHTLY
AGAINST SUPPLY AIR DUCT
Figure 9. Duct Connector Tabs
8. Bend both tabs on the mounting plate up 90° as shown
in Figure 9.
9. Seal all connections with industrial grade sealing tape
or liquid sealant.
NOTE:
Requirements for sealing ductwork vary
from region to region. Consult with local codes for
requirements specifi c to your area.
Narrow Duct Connectors
This attachment method should be used if there is
insuffi cient clearance to bend the tabs on a standard 12”
duct connector.
1. Score and cut the top of the supply air duct as indicated
in Option 1 or Option 2 (Figure 10). With Option 1
choice, cut out the metal from the shaded area.
2. Fold the two fl aps (Options 1 or 2) up to form the
opening for the duct connector.
3. Install the duct connector with the bottom tabs
extending into the supply air duct.
4. Bend the tabs on the bottom of the duct connector
upwards and as tight as possible against the supply
air duct (Figure 11, page 11).
5. Form the fl aps (Options 1 or 2) up against the duct
connector as tight as possible.
6. Secure the duct connector fl aps to the supply air
duct with staples (3 minimum) or if a 2x block/joist is
not provided, use sheet metal screws (2 minimum).
NOTE:
The duct connector tabs may be attached to
the air duct with sheet metal screws or other suitable
fasteners as long as the duct connector and the air
duct are securely attached.
