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Most Recent LiftMaster 3840 Questions
Door Will Not Close!
When I press the button to close door, it goes down a couple inches and then reverses and goes back ...
When I press the button to close door, it goes down a couple inches and then reverses and goes back ...
(Posted by jmbfoto 9 years ago)
Will A 485 Lm Battery For A Model 3850 Work On A Model 3840?
I need a new battery for my garage opener, model 3840. All of the batteries I have seen are 485LM fo...
I need a new battery for my garage opener, model 3840. All of the batteries I have seen are 485LM fo...
(Posted by kdmeacham 9 years ago)
Where Can I Find Complete Technical Info For A Liftmaster 3840 Garage Door Opene
Need to know Logic Board jumper settings and communications protocol for remote devices.
Need to know Logic Board jumper settings and communications protocol for remote devices.
(Posted by user754642 11 years ago)
Popular LiftMaster 3840 Manual Pages
3840 Manual - Page 1
®
GARAGE DOOR OPENER Model 3840
For Residential Use Only
Com Details
The Chamberlain Group, Inc. 845 Larch Avenue Elmhurst, Illinois 60126-1196 www.LiftMaster.com
patible with
See Page 30 for
Owner's Manual
■ 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 ...
3840 Manual - Page 2
...instructions 26
Using your garage door opener 28
Using the remote control 29
The remote control battery 29
Troubleshooting 29
Standby Power (Optional 30
Having a problem 31
Diagnostic chart 32-33
Programming
34-35
To add or reprogram a hand-held remote control . . . . . 34
To erase all codes 34
3-Button remotes 34
To add, reprogram or change
a Keyless Entry PIN 35
Repair...
3840 Manual - Page 5
... parts illustrated below .
Parts may be stuck in two cartons which anything is also listed below . Hardware for installation
Accessories will depend on the model purchased. LOCK
LIGHT
Smart Control Panel®
SECURITY✚® 3-Button Remote Control
CEILING MOUNT ONLY UP
Remote Control Visor Clip
Header Bracket
Rail
2 Conductor Bell Wire White & White/Red
Curved Door...
3840 Manual - Page 7
..., rings or loose clothing while installing or servicing opener. Place entrapment warning label on properly balanced and lubricated garage door. Mount emergency release handle 6 feet (1.83 m) above floor.
6. To avoid SERIOUS PERSONAL INJURY or DEATH from ALL moving parts of garage door.
12. NEVER connect garage door opener to power source until instructed to avoid entanglement.
5. READ...
3840 Manual - Page 9
....
Drill 3/16" pilot holes and fasten bracket securely to a structural support with the hardware provided. Finished Ceiling - Do not install the header bracket over drywall. Make sure the arrow is pointing toward the ceiling). • Mark the vertical set of Garage Door
CEILING HEADER BRACKET INSTALLATION • Extend the vertical centerline onto the ceiling as shown...
3840 Manual - Page 11
... be unobstructed. above the floor. No part of sectional garage doors without additional hardware. The units must be installed inside the garage
Safety Reversing Sensor 6" (15 cm) max.
This
required safety device MUST NOT be installed on the wall, the brackets must be connected and aligned correctly before the garage door opener will flash 10 times. Either can be...
3840 Manual - Page 15
...Operate the door manually.
Yours may be used if installing ANY brackets into masonry. Concrete anchors MUST be different. On finished ceilings (Figure 2 and Figure 3), attach a sturdy metal bracket to required lengths.
3. FINISHED CEILING - Check to the structural support.
2. If the door hits the rail, raise the header bracket. INSTALLATION STEP 6
Hang the Opener
Three...
3840 Manual - Page 16
... closing garage door:
• Install door control within sight of door, at a minimum height of 5 feet (1.5 m) where small children cannot reach, away from moving parts of door.
• NEVER permit children to operate or play with door control push buttons or remote control transmitters.
• Activate door ONLY when it can be mounted to wall near the garage door, you have any trouble...
3840 Manual - Page 18
...) before spade terminals. • Remove the power cord from electrocution or fire:
• Be sure power is required by your garage door opener has a grounding type plug with ALL local electrical and building codes.
• NEVER use an extension cord, 2-wire adapter, or change plug in the white or white/black wires. When the...
3840 Manual - Page 26
...-held remote control have been factory-set to pull garage door open garage door. If the sensor is not installed, or is CLOSED. NEVER use , randomly accessing over 100 billion new codes. If possible, use emergency release handle unless garage doorway is clear of the following conditions: when the opener is complete. If open . 2. READ AND FOLLOW ALL WARNINGS AND INSTRUCTIONS.
2. ALWAYS...
3840 Manual - Page 29
...
With 315 MHz Security✚® remote controls, a remote push button can be oversensitized. After the opener lights flash, release all buttons. Test by pressing a button. The opener lights should not move. To reduce risk of the holder for removal. The 3V2016 lithium batteries for changing the code setting or replacing the battery.
This allows the sensor...
3840 Manual - Page 30
... for replacement battery. • DO NOT dispose of time.
Standby Power (Optional)
OPERATING INSTRUCTIONS 1.
Check with worklight off of time.
30 A fully charged battery supplies 12 Vdc to the motor unit for one to persons: • Disconnect ALL electric and battery power BEFORE
performing ANY service or maintenance. • Use ONLY LiftMaster part # 485LM for service...
3840 Manual - Page 31
... before the garage door opener will still not activate your Smart Control Panel® is not lit properly: • Check battery connections. HAVING A PROBLEM?
1. Refer to Adjustment Step 2, Setting the Force.
4.
My lights will not close and the light bulbs blink on when the safety sensor beam has been obstructed. Refer to Adjustment Step 1, Program the...
3840 Manual - Page 38
... strip. Enables homeowner to protect LiftMaster® garage door openers against damage from outside by adding additional sensor modules. OPEN
3-Button Mini-Remote Control with NO access door. Garage Door Monitor: Security for visitors or service persons. Also can store up to precisely park vehicles in control panel is open garage door manually from outside radio signals while...
3840 Manual - Page 40
... THE DOOR SPRINGS, DOOR ROLLERS, DOOR ALIGNMENT OR HINGES. SIMPLY DIAL
OUR TOLL FREE NUMBER:
1-800-528-9131
www.liftmaster.com
For professional installation, parts and service, contact your area. Look for him in materials and/or workmanship for the lifetime of -purchase receipt with new or factory-rebuilt parts at prevailing prices and you will be repaired or replaced (at...
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