Master Lock ATS 211 - Manual (Page 11)

Installation Step 4
Position the Opener
To prevent damage to steel, aluminum,
fiberglass or glass panel doors, do not rest the
opener on the door without using a 2x4.
11
CAUTION
Trolley
Trolley
Release Arm
• If the top panel hits the trolley when you raise
the door, pull down on the trolley release arm
to disconnect the inner and outer sections. The
trolley can remain disconnected until Step 12
is completed.
A 2x4 laid flat is convenient for setting an ideal
door-to-rail distance.
• 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.
Rail
2x4
Door
Stepladder