Craftsman 139.53993D - Manual (Page 3)

Preparing your garage door
Before you begin:
• Disable locks.
• Remove any ropes connected to garage door.
• Complete the following test to make sure your
garage door is balanced and is not sticking or binding;
1. Lift the door about halfway as shown. Release the
door. If balanced, it should stay in place, supported
entirely by its springs.
2. Raise and lower the door to see if there is any
binding or sticking.
If your door binds, sticks, or is out of balance, call a
trained door systems technician.
A
WARNING
To prevent possible SERIOUS INJURY or DEATH:
• ALWAYS call a trained door systems technician if garage
door binds, sticks, or is out of balance. An unbalanced
garage door may not reverse when required.
• NEVER try to loosen, move or adjust garage door, door
springs, cables, pulleys, brackets or their hardware, all of
which are under EXTREME tension.
• Disable ALL locks and remove ALL ropes connected to
garage door BEFORE installing and operating garage door
opener to avoid entanglement.
CAUTION
To prevent damage to garage door and opener:
• ALWAYS disable locks BEFORE installing and operating the
opener.
• ONLY operate garage door opener at 120V, 60 FIz to avoid
malfunction and damage.
Tools needed
During assembly, installation and adjustment of the
opener, instructions will call for hand tools as illustrated
below.