Chamberlain HD520EV User Manual page 3

Preparation
Additional Items You May Need:
Survey your garage area to see if you will need any of the following items:
(2) 2X4 PIECES OF WOOD
n
May be used to fasten the header bracket to the structural supports. Also used to position the
garage door opener during installation and for testing the safety reversing sensors.
SUPPORT BRACKET AND FASTENING HARDWARE
n
Must be used if you have a finished ceiling in your garage.
EXTENSION BRACKETS (MODEL 041A5281-1) OR WOOD BLOCKS
n
Depending upon garage construction, extension brackets or wood blocks may be needed to
install the safety reversing sensor.
FASTENING HARDWARE
n
Alternate floor mounting of the safety reversing sensor will require hardware not provided.
OUTSIDE QUICK RELEASE (MODEL 7702CB)
n
Required for a garage with NO access door.
DOOR REINFORCEMENT
n
Required if you have a lightweight steel, aluminum, fiberglass or glass panel door.
RAIL EXTENSION KIT
n
Required if your garage door is more than 7 feet (2.13 m) high.
Tools Needed
7/32
3/16
5/16
1/2
3/8
7/16
2
1/2
7/16