Connect square duct to plenum

Before you start

• Confirm the duct size, end construction, pressure class, seal class, and joint shown on the approved shop drawing.
• Inspect both duct ends for crushed corners, torn locks, bowed panels, loose reinforcement, or shop damage before lifting them into place.
• Make sure the supports are already installed or the sections are otherwise held so the joint is not carrying the weight of the run.
• Stage the correct S-cleats, drive cleats, sealant, hand tools, clamps, and access equipment before starting the joint.

Lay it out

1. Verify the plenum dimensions, inlet orientation, access panel, damper, filter, and service-clearance requirements.
2. Confirm the connection opening is reinforced and intended for S-and-drive construction.
3. Plan supports so the plenum casing carries no branch or main-duct weight.

Set and support it

1. Hang or set the plenum level and square before connecting duct.
2. Support the incoming duct close to the plenum connection.
3. Align the duct opening to the plenum without prying or bowing the casing panel.

Make the connection

1. 1

   Fit the top and bottom S-cleats to the mating edges.

2. 2

   Bring the duct to the plenum and align all four corners.

3. 3

   Start both side drives and seat them evenly while watching the plenum panel.

4. 4

   Finish the drive ends and seal corners, seams, and any required perimeter.

5. 5

   Check that internal dampers, pattern controllers, or filters remain clear.

6. 6

   Verify service panels can still open.