Chamberlain 248735 3/4 HP - Manual (Page 5)

5
Access
Door
Safety
Reversing Sensor
Safety
Reversing
Sensor
Gap between floor
and bottom of door
must not exceed 1/4" (6 mm).
Door
Bracket
Straight
Door
Arm
Garage
Door
CLOSED POSITION
Header
Bracket
Curved
Door Arm
Chain
Emergency
Release
Rope &
Handle
Cable
Rail
Trolley Stop Bolt
Header
Wall
Planning (Continued)
ONE-PIECE DOOR INSTALLATIONS
• Generally, a one-piece door does not require
reinforcement. If your door is lightweight, refer to the
information relating to sectional doors in Installation
Step 11.
• Depending on your door’s construction, you may need
additional mounting hardware for the door bracket
(Step 11).
Safety Reversing Sensor
Access
Door
FINISHED CEILING
Support bracket
& fastening
hardware is required.
See page 16.
Safety Reversing
Sensor
Header Wall
Gap between floor
and bottom of door must not exceed 1/4" (6 mm).
Wall-mounted
Door Control
Rail
Motor Unit
Slack in chain tension
is normal when garage
door is closed.
ONE-PIECE DOOR WITHOUT TRACK
Header
Bracket
Trolley
Straight
Door
Arm
Emergency
Release
Rope & Handle
Door Bracket
Curved
Door
Arm
Header
Wall
Cable
Rail
Garage Door
Trolley Stop Bolt
CLOSED POSITION
Without a properly working safety reversal system, persons
(particularly small children) could be SERIOUSLY INJURED or
KILLED by a closing garage door.
• The gap between the bottom of the garage door and the
floor MUST NOT exceed 1/4" (6 mm). Otherwise, the safety
reversal system may not work properly.
• The floor or the garage door MUST be repaired to eliminate
the gap.
ONE-PIECE DOOR WITH TRACK