Chamberlain 3275 Garage Door Opener User Manual


 
22
ALL ONE-PIECE DOORS
1. Assemble the door arm, Figure 5:
IMPORTANT: The groove on the straight door arm
MUST face away from the curved door arm (Figure 5).
• 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, Figure 6:
• On one-piece doors, before connecting the door arm
to the trolley, the travel limits must be adjusted. Limit
adjust ment screws are located on the left side panel
as shown on page 23. Follow adjustment procedures
below.
• Open door adjustment: decrease UP travel limit
- Turn the UP limit adjustment screw
counter-clockwise 4 turns.
- Press the Door Control push button. The trolley will
travel to the fully open position.
- Manually raise the door to the open position (parallel
to the fl oor), and lift the door arm to the trolley. The
arm should touch the trolley just in back of the door
arm connector hole. Refer to the fully open trolley/
door arm positions in the illustration. If the arm does
not extend far enough, adjust the limit further. One
full turn equals 3" (7.5 cm) of trolley travel.
• Closed door adjustment: decrease DOWN
travel limit
- Turn the DOWN limit adjustment screw clockwise
4 complete turns.
- Press the Door Control push button. The trolley will
travel to the fully closed position.
- 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. Refer to the fully
closed trolley/door arm positions in the illustration. If
the arm is behind the connector hole, adjust the limit
further. One full turn equals 3" (7.5 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 fl oor.
NOTE: When setting the up limit on the following page, the
door should not have a "backward" slant when fully open
as illustrated below. 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.
Door
Bracket
Straight
Arm
Bolts
5/16"-18x7/8
Curved
Door
Arm
Lock
Washers
5/16"
Nuts
5/16"-18
Ring
Fastener
Clevis Pin
5/16"x1-1/4"
Figure 5
Straight
Door
Arm
Curved
Door
Arm
(Groove
facing out)
Straight
Door
Arm
Curved
Door
Arm
CORRECT INCORRECT
Figure 6
Door Arm
Door Arm
Closed Door
Door Arm
Connector Hole
Inner Trolley
Inner Trolley
Outer Trolley
Outer Trolley
Emergency Release Handle
Open Door
Correct Angle
Door with
Backward Slant (Incorrect)