. Use ONLY A19 incandescent(100W maximum) or compactfluorescent(26W maximum) light bulbs. NOTE: Ifyouareinstallingthegaragedooropeneronaone-piecedoor,visitwww.liftmaster.comforinstallationinstructions. . . Garage door installation and wiring MUST be in compliance with ALL local electrical and building codes. . 1.1C Carefullymeasure the position ofboth, 1.2C Attach the sensor bracketsto the floor, 1.3C Slide the carriage boltinto the sloton, 1.4C Insertthe boltthrough the hole in the sensor, bracketand attach with the wing nut.The lens, 2.2A Strip 7/16 inch (11 mm) ofinsulation, 2.3A Insertthe white wiresinto the white terminal on, alreadyhaswiresinstalled for the safetyreversing, the garage door opener.Insertthe white/black, wiresinto the greyterminal on the garage door, opener.To insertor remove the wiresfromthe. . Measure the distance fromeach side ofthe motor unitto the structural support. 1.1B Position the sensor bracketagainstthe, 1.2B Drill 3/16 inch pilotholesfor each sensor 1.3B, 1.4B Insertthe boltthrough the hole in the sensor, other.Make sure the lensisnotobstructed by. 14.DO NOTenable the Timer-to-Close functionalityifoperating either one-piece or swinging garage doors.To be enabled ONLY when operating a sectional door. . . Attach the straightdoor armto the outer trolleyusing the clevispin.Attach with the ring fastener. – any latin characters (a-z, A-Z)– any numbers (0-9)– special characters ("-", "_" and "."). . Run the white and red/white wire fromthe door control to the garage door opener.Attach the wire to the wall and ceiling with the staples(notapplicable for gang boxor. . 9.1Close the door.Disconnectthe trolleyby pulling the emergencyrelease handle. Also for: Liftmaster premium 8355-1/2 hp. . Insertan A19 incandescent(100Wmaximum) or compactfluorescent(26W,100W equivalent) light bulb into the lightsocket. 9.2Attach the straightdoor armto the outer trolleyusing the clevispin.Attach with the ring fastener. Donot installthe headerbracket overdrywall.If installinginto masonry,use concrete anchors (not provided). A horizontal and vertical reinforcement is needed for lightweight garage doors (ﬁberglass, aluminum, steel, doors with glass panel, etc.) . . 1.3Open your door to the highestpointoftravel asshown.Drawan intersecting horizontal line on the header wall 2" (5 cm) above the high point.Thisheightwill provide travel clearance for the top edge ofthe door. Washered Bolt 5/16"-18x1/2" (Mounted in the garage door opener). View and Download Chamberlain 8355 manual online. To avoid installation difficulties, do not activate the garage door opener at this time. The opener must be grounded. . •DO NOTuse shortneckor specialtylightbulbs. 10.Place entrapmentwarning label on wall nextto garage door control. 4.Disable ALL locksand remove ALL ropesconnected to garage door BEFORE installing opener to avoid entanglement. . 11.Place manual release/safetyreverse testlabel in plain viewon inside ofgarage door. . . . You can attach the header bracketeither to the wall above the garage door,or to the ceiling. . 6.1Pull on the top center ofthe lightlensand rotate the lightlensdown. . NOTE: Accessories will vary depending on the garage door opener model purchased. Youcanfastenthe headerbracket within4 feet (1.22 m) of the left orright of the door centeronly if a torsionspringorcenterbearingplate is inthe way; oryoucanattachit to the ceilingwhenclearance is minimal. . NEVERconnectgarage door opener to power source until instructed to do so. . Strip 7/16 inch (11 mm) ofinsulation fromthe end ofthe wire near the garage door opener. NOTE: Yourproductmaylookdifferentthan movingpartsofthedoortheillustrations. . Place manual release/safetyreverse testlabel in plain viewon inside ofgarage door. . •Header bracketMUSTbe RIGIDLY fastened to structural supporton header wall or ceiling,otherwise garage door might NOTreverse when required.DO NOT install header bracketover drywall. . ■ Fasten the manual near the garage door after installation. (Figure 2), • Alternately,use two 5/16" bolts,lockwashersand nuts(notprovided). 2.1Run the white and red/white wire fromthe door control to the garage door opener.Attach the wire to the wall and ceiling with the staples(notapplicable for gang boxor pre-wired installations).Do notpierce the wire with the staple asthismaycause a shortor an open circuit. The safety reversingsensors must be connectedandalignedcorrectly before the garage dooropenerwillmove inthe downdirection. To make a permanent connection through the 7/8 inch hole in the top of the motor unit (according to local code): 1.1B Remove the motor unit cover screws and set the cover aside. . NOTE: Forgangboxinstallationsitisnotnecessarytodrillholesorinstallthedrywallanchors.Usetheexistingholesinthegangbox. . Remove the 2x4.Operate the door manually.Ifthe door hitsthe rail,raise the header bracket. . . Withouta properlyinstalled safetyreversal system,persons(particularlysmall children) could be SERIOUSLY INJUREDor KILLEDbya closing garage door. . . View and Download LiftMaster 8355 instruction manual online. •ALWAYS call a trained door systems technician ifgarage door binds,sticks,or is outofbalance.An unbalanced garage door mightNOTreverse when required. . 9.4Align the straightdoor armwith the curved door arm.Selecttwo aligned holes(asfar apartaspossible) and attach using the bolts,nutsand lock washers. DO NOTuse incandescentbulbslarger than 100W. . Premium Series Belt Drive Garage Door Opener. To prevent possible SERIOUS INJURY or DEATH from electrocution or fire: •Be sure power is NOT connected to the opener, and disconnect power to circuit BEFORE removing cover to establish permanent wiring connection. ■ The model number label is located on the front panel of your garage door opener. 2.4B Atthe garage door opener,strip 7/16 inch (11 mm) ofinsulation fromeach end ofthe wirespreviouslychosen for the, 2.5B Insertthe wiresconnected to the white safetysensor wiresto the. . 1.3B Connect the black (line) wire to the screw on the brass terminal; the white (neutral) wire to the screw on the silver terminal; and the ground wire to the green ground screw. IFTHE AMBERLEDONTHE SENDING SENSORIS NOTGLOWING: IFTHE GREENLEDONTHE RECEIVING SENSORIS NOTGLOWING: Make sure the sensor has been wired correctly: white wires to white terminal and white/black wires to grey terminal. . To preventpossible SERIOUS INJURY or DEATHfroma falling garage door: •Ifpossible,use emergencyrelease handle to disengage trolleyONLY when garage door is CLOSED.Weakor broken springsor unbalanced door could resultin an open door falling rapidlyand/or unexpectedly.