Chamberlain 1280 - 1/2 HP - Manual (Page 4)

4
You may find it helpful to refer back to this page as you proceed with the installation of your opener.
Safety Reversing Sensor
Horizontal and vertical reinforcement
is needed for lightweight garage doors
(fiberglass, steel, aluminum, door with glass panels, etc.).
See page 20 for details.
Support bracket &
fastening hardware
is required.
See page 13.
— — — — — — — —
Door Center
Header Wall
Safety
Reversing
Sensor
Floor must be level
across width of door
FINISHED CEILING
Extension Spring
Torsion Spring
Access Door
OR OR
One-Piece Door-Extension Spring
Header
Wall
Door
Track
Slack in belt tension
is normal when
garage door is closed.
Before you begin, survey your garage area to see whether any of the conditions below apply to your installation.
SECTIONAL Door or ONE-PIECE Door
with Track Installation
Safety Reversing Sensor
FINISHED CEILING
Support bracket
& fastening
hardware is required.
See page 13.
Safety
Reversing
Sensor
Header
Wall
Access Door
Gap between floor and bottom of
door must not exceed 1/4".
ONE-PIECE Door Without Track Installation