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CONTENTS
Preparation . . . . . . . . . . . . . . . .2-3
Assembly . . . . . . . . . . . . . . . . .4-5
Installation . . . . . . . . . . . . . . . 6-13
Install the Door Control . . . . . . 14-15
Install the Protector System
®
. . 16-19
Power. . . . . . . . . . . . . . . . . . 20-21
Adjustments . . . . . . . . . . . . . 22-24
Battery Backup*. . . . . . . . . . . 25-26
Operation . . . . . . . . . . . . . . . . . 27
Features . . . . . . . . . . . . . . . . . . 28
Door Control . . . . . . . . . . . . . 29-30
Remote Control . . . . . . . . . . . 31-32
To Erase the Memory . . . . . . . . . 32
To Open the Door Manually . . . . . 33
Maintenance . . . . . . . . . . . . . . . 34
Troubleshooting. . . . . . . . . . . 35-36
Accessories. . . . . . . . . . . . . . . . 37
Warranty. . . . . . . . . . . . . . . . . . 38
Repair Parts . . . . . . . . . . . . . 39-41
* If applicable
ELITE Series
Garage Door Opener
LiftMaster
845 Larch Avenue
Elmhurst, Illinois 60126-1196
■
Please read this manual and the enclosed safety materials carefully!
■
Fasten the manual near the garage door after installation.
■
The door WILL NOT CLOSE unless the Protector System
®
is connected and properly
aligned.
■
Periodic checks of the garage door opener are required to ensure safe operation.
■
The model number label is located on the left side panel of your garage door opener.
■
This garage door opener is ONLY compatible with MyQ
®
and Security
✚
2.0™
accessories.
■
DO NOT enable the Timer-to-Close feature if you are installing the garage door
opener on a one-piece door. The Timer-to-Close is to be used ONLY with sectional
doors.
NOTE:
If you are installing the garage door opener on a one-piece door, visit
www.LiftMaster.com for installation instructions.
www.LiftMaster.com
Serial Number:
Date of Purchase:
Models
• 8550 - DC Belt Drive
with Battery Backup
• 8557 - 3/4 hp
Belt Drive
FOR RESIDENTIAL USE ONLY
Write down the following information for
future reference:
.