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GT20 8300-8350 Overhead Concealed Operator Installation Manual
www.NabcoEntrances.com
P/N C-00183
Rev 8-31-16
CHAPTER 5: INSTALL THE HEADER
The Overhead Concealed (OHC) Operator Assembly is installed inside the Door Frame (directly underneath the top, between (2) Jamb
Tubes). The GT20 Operator can swing the Door Panel:
Out to the Exterior, or In to the Interior.
DN 1270
Figure 3 Overhead Concealed Operator Assembly
SECTION 5 .1 Prep the Jamb Tubes
1. Measure the full height of existing Swing door.
2. Obtain and then place the Jamb Drilling Template at the top of Jamb Tube so it is flush.
3. Align the center to the previously drawn center mark.
4. Adhere the Jamb Drilling Template to each Jamb Tube.
a. The Jamb Drilling Template is removable.
Figure 4 Adhere Jamb Drilling Template
DN 0469
Line marking
Center of Jamb Tube
Jamb Drilling Template
5. Drill (4) .391 diameter holes through (4) clearly marked (A)s on the Template. Countersink each screw hole.
6. Obtain (4) Rivnuts provided by NABCO. Install (1) Rivnut into each drilled .391 hole.
7. Drill (1) 1-1/4 inch diameter hole through (1 of 2) clearly marked (B)s on the Template to allow incoming 120 VAC Power.
a. The 120 VAC incoming power must be routed through the Strike Jamb, only.
8. Remove the Template from the Strike Jamb, then adhere same Template to the Pivot Jamb. Repeat steps.
SECTION 5 .2 Install the Header to Jamb Tubes
1. Determine which Jamb tube is the Pivot Jamb and the Strike Jamb.
X
Swing door pivots on side of Pivot Jamb.
X
Swing door locks on side of Strike Jamb.
2. Position each Jamb tube at both sides of the Header. Be sure to orientate the frame in relation to the outside of building/room.
Figure 5 Layout Header and Jamb Tubes
DN 0468
Top of Header
Rough
Opening
Interior Side of Building
Jamb Tube
ON
3. Secure Header to both Jamb Tubes with (8) 1/4-20 x 3/4 inch Hex Head Cap Screws and (8) 1/4 inch Star Washers from the
Parts bag provided within the Header.