Chamberlain 248730 - Manual (Page 20)

19
Installation
STEP 9 Connect the door arm to the trolley (continued)
OPTION B
ONE-PIECE DOORS
1. Assemble the door arm, Figure 1:
IMPORTANT: The groove on the straight door arm MUST face away from the curved door arm.
• Fasten the straight and curved door arm sections together to the longest possible length (with a 2 or 3
hole overlap).
• With the door closed, connect the straight door arm section to the door bracket with the 5/16"x1-1/4"
clevis pin. Secure with a ring fastener.
2. Adjustment procedures:
• On one-piece doors, before connecting the door arm to the trolley, the travel limits must be adjusted.
Limit adjustment screws are located on the left side panel as shown on page 28. Follow adjustment
procedures below.
• Open door adjustment : Decrease UP travel limit
n Turn the UP limit adjustment screw counterclockwise 4 turns.
n Press the door control push button. The trolley will travel to the fully open position.
n Manually raise the door to the open position (parallel to the floor), and lift the door arm to the
trolley. The arm should touch the trolley just in the back of the door arm connector hole. If the
arm does not extend far enough, adjust the limit further. One full turn equals 2" (5 cm) of trolley
travel.
• Closed door adjustment : Decrease DOWN travel limit
n Turn the DOWN limit adjustment screw clockwise 4 complete turns.
n Press the door control push button. The trolley will travel to the fully closed position.
n Manually close the door and lift the door arm to the trolley. The arm should touch the trolley
just ahead of the door arm connector hole. If the arm is behind the connector hole, adjust the
limit further. One full turn equals 2" (5 cm) of trolley travel.
3. Connect the door arm to the trolley:
• Close the door and join the curved arm to the connector hole in the trolley with the remaining clevis pin.
It may be necessary to lift the door slightly to make the connection. Secure with a ring fastener.
• Run the opener through a complete travel cycle. If the door has a slight “backward” slant in full open
position as shown in the illustration, decrease the UP limit until the door is parallel to the floor
(Figure 2).
NOTE: A slight backward slant will cause unnecessary bucking and/or jerking operation as the door is
being opened or closed from the fully open position. See page 28 for adjustments.
HARDWARE
Hex Bolt 5/16"-18x7/8"
Nut 5/16"-18
Lock Washer
5/16" -18
Clevis Pin 5/16"x1" Clevis Pin 5/16"x1-1/4"
Ring Fastener
FIGURE 1: Door Closed
FIGURE 2 Inner Trolley
Outer Trolley
Open Door Door with Bacward Slant (Incorrect)
Door Arm
Nut
Ring
Fastener
Ring Fastener
Lock Washer
Clevis Pin
5/16"x1-1/4"
Hex Bolt
Clevis Pin
5/16"x1"
One-Piece Door without Track
One-Piece Door with Track
Ring
Fastener
Ring Fastener
Nut
Lock Washer
Clevis Pin
5/16"x1-1/4"
Hex Bolt
Clevis Pin
5/16"x1"
CORRECT
Straight
Door
Arm
(Groove
facing
out)
Curved
Door
Arm
INCORRECT
Straight
Door
Arm
Curved
Door
Arm