Chamberlain 2255-2 - Manual (Page 11)

11
ONE-PIECE DOOR WITHOUT TRACK
A 2x4 on its side is convenient for setting an ideal
door-to-rail distance.
• Remove foam packaging.
• Raise the opener onto a stepladder. You will need
help at this point if the ladder is not tall enough.
• Open the door all the way and place a 2x4 on its
side on the top section of the door beneath the rail.
• The top of the door should be level with the top of
the motor unit. Do not position the opener more
than 4" (10 cm) above this point.
INSTALLATION STEP 4
Position the Opener
Follow instructions which apply to your door type as
illustrated.
SECTIONAL DOOR OR ONE-PIECE DOOR WITH
TRACK
A 2x4 laid flat is convenient for setting an ideal
door-to-rail distance.
• Remove foam packaging.
• Raise the opener onto a stepladder. You will need
help at this point if the ladder is not tall enough.
• Open the door all the way and place a 2x4 laid flat
on the top section beneath the rail.
• If the top section or panel hits the trolley when you
raise the door, pull down on the trolley release arm
to disconnect inner and outer sections. Slide the
outer trolley toward the motor unit. The trolley can
remain disconnected until Installation Step 12
is completed.
Trolley
Release Arm
ENGAGED RELEASED
To prevent damage to garage door, rest garage door
opener rail on 2x4 placed on top section of door.
WARNING
CAUTION WARNING
WARNING
Rail
Door
2x4 is used to determine
the correct mounting height
from ceiling.
Header
Bracket
Top of Door
2x4 is used to determine
the correct mounting height
from ceiling.