Chamberlain 3850 User Manual

The Chamberlain Group, Inc.845 Larch AvenueElmhurst, Illinois 60126-1196www.liftmaster.comGARAGE DOOR OPENERModel 3850For Residential Use Only Owner’s

10Clevis Pin5/16"x2-3/4"Ring FastenerHeaderBracketBelt PulleyBracketTemporarySupportHeader WallGarageDoorClevis Pin5/16"x2-3/4"Ri

11ONE-PIECE DOOR WITHOUT TRACK• With the door fully open and parallel to the floor,measure the distance from the floor to the top of thedoor.• Using a

12INSTALLATION STEP 5Hang the OpenerThree representative installations are shown. Yours maybe different. Hanging brackets should be angled (Figure 1)t

13INSTALLATION STEP 6Install the Control ConsoleLocate control console within sight of door, at a minimumheight of 5' (1.5 m) where small childre

14LensHinge100 Watt (Max)Standard Light BulbRelease Tab100 Watt (Max)Standard Light BulbINSTALLATION STEP 7Install the Battery Backup (Optional)• Make

15INSTALLATION STEP 10Electrical RequirementsTo avoid installation difficulties, do not run the openerat this time.To reduce the risk of electric shoc

16Facing the door from inside the garageINSTALLATION STEP 11Install The Protector System®The safety reversing sensor must be connected andaligned corr

17DOOR TRACK MOUNT (RIGHT SIDE)IndicatorLightLensLip SensorBracketDoorTrackFLOOR MOUNT (RIGHT SIDE)WALL MOUNT (RIGHT SIDE)IndicatorLightSensorBracketL

Carriage Bolt 1/4"-20x1/2"LensWing Nut1/4"-20Figure 5MOUNTING AND WIRING THE SAFETY REVERSINGSENSORS• Slide a 1/4"-20x1/2" ca

19INSTALLATION STEP 12Fasten the Door Bracket Follow instructions which apply to your door type asillustrated below or on the following page.A horizon

2Introduction 2-5Safety symbol and signal word review . . . . . . . . . . . . . .2Preparing your garage door . . . . . . . . . . . . . . . . . . . .

20Header WallVerticalCenterline ofGarage DoorFinished CeilingOptionalPlacementof DoorBracketHeaderBracketDoorBracket2x4 SupportFor a door with no expo

21INSTALLATION STEP 13Connect Door Arm to TrolleyFollow instructions which apply to your door type asillustrated below and on the following page.SECTI

22Door ArmDoor ArmConnector HoleClosedDoorOuter TrolleyEmergency Release HandleInner TrolleyOuter TrolleyOpen DoorDoor ArmCorrect AngleDoor withBackwa

ADJUSTMENT STEP 1Program the Travel LimitsTravel limits regulate the points at which the door willstop when moving up or down. Follow the steps belowt

Black ButtonPurple ButtonPush Purple button twice to enter unit into Indicator Light24ADJUSTMENT STEP 2Setting the ForceThe force setting button is lo

25Without a properly installed safety reversal system, persons(particularly small children) could be SERIOUSLY INJURED orKILLED by a closing garage do

Using Your Garage Door OpenerYour Security✚®opener and hand-held remote controlhave been factory-set to a matching code which changeswith each use, ra

Using the Wall-Mounted Control ConsoleTHE LCD MOTION DETECTING CONTROL CONSOLEPress the push bar toopen or close thedoor. Press again toreverse the do

28Using the Remote ControlNOTE: To activate the remote control functions, pull outthe plastic pull tab protruding from the remote controlhousing.This

29NOTE: LED is most visible with worklight off.GREEN LED:All systems are normal.• A solid LED light indicates the battery is fully charged.• A flashin

3To prevent damage to garage door and opener:• ALWAYS disable locks BEFORE installing and operating theopener. • ONLY operate garage door opener at 12

30CARE OF YOUR OPENERMAINTENANCE SCHEDULEOnce a Month• Manually operate door. If it is unbalanced or binding, calla trained door systems technician.•

31Having a Problem (Troubleshooting)NOTE: Always unplug battery prior to troubleshooting.1. My door will not close and the light bulbs blink onmy moto

32Bell WireSafety Reversing SensorDiagnosticsLocated OnMotor Unit“Learn”Button LED or DiagnosticLED “Learn” ButtonInstalled Safety Reversing SensorYou

33Meaning: This message will appear if the Safety Reversing Sensors are out ofalignment, if they are blocked or if the wiring is disconnected. To clea

*3-Button RemotesIf provided with your garage door opener, the largebutton is factoryprogrammed to operate it.Additional buttons on anySecurity✚®3-but

1. Press and release the “learn” buttonon motor unit. The learn indicatorlight will glow steadily for 30seconds.2. Within 30 seconds, enter a four dig

3625613784KEY PARTNO. NO. DESCRIPTION1 4A1008 Master link kit2 41B5424 Belt pulley bracket3 41B3869-1 Complete trolley assembly4 109B33 Trolley clip5

37211173864591010KEY PARTNO. NO. DESCRIPTION1 41C76 Belt cap and sprocket2 41B4245 Line cord3 41B4375-3 Terminal block with screws4 41A6281 Wire harne

38ACCESSORIES CLOSEDOPEN374LM370LM915LM395LM990LM1702LMOutside Quick Release:Required for a garage with NO accessdoor. Enables homeowner to opengarage

39NOTES

4SECTIONAL DOOR INSTALLATIONPlanningIdentify the type and height of your garage door. Survey your garage area to see if any of the conditions below ap

© 2007, The Chamberlain Group, Inc.114A3406 All Rights ReservedHOW TO ORDERREPAIR PARTSSelling prices will be furnished on request or parts will beshi

5Straight DoorArm SectionCurved DoorArm SectionSafety LabelsandLiteratureHeader BracketUPCEILING MOUNT ONLYBelt Cap Retainer2-Conductor Bell WireWhite

6ASSEMBLY STEP 1Attach the Rail to the Motor UnitTo avoid installation difficulties, do not run the garagedoor opener until instructed to do so.• Remo

7ASSEMBLY STEP 3Attach the Belt Cap Retainer• Position the belt cap retainer over the motor unit beltpulley so the three holes in cap align with the t

8INSTALLATION STEP 1Determine the Header BracketLocationInstallation procedures vary according to garage doortypes. Follow the instructions which appl

9INSTALLATION STEP 2Install the Header BracketYou can attach the header bracket either to the wall abovethe garage door, or to the ceiling. Follow the