[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-653694-105":59,"doc-detail-653694-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","chamberlain-garage-door-opener-model-248739-owners-manual","Chamberlain Garage Door Opener Model 248739 - Owner’s Manual","","Owner’s Manual for the Chamberlain Group, Inc. garage door opener model 248739, providing residential-use installation, safety, and operation guidance. Includes key safety symbol and signal word review, preparation steps for the existing garage door, and detailed planning for installation requirements. Covers assembly and installation procedures, electrical requirements, testing of safety reversal and Protector System, plus operation, troubleshooting, programming of remotes, repair parts, and warranty information.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":30,"@type":76,"position":81},"https://docshare.wps.com/document/technology/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/chamberlain-garage-door-opener-model-248739-owners-manual/653694/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/chamberlain-garage-door-opener-model-248739-owners-manual/653694.png","ImageObject",300,407,{"name":92,"@type":93},"Hazel","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-11-01","2026-10-25",true,{"@type":102,"interactionType":103,"userInteractionCount":39},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What is required for the garage door to close safely?","Question",{"text":112,"@type":113},"The door will not close unless The Protector System® is connected and properly aligned. Periodic checks of the opener are also required to ensure safe operation.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How do you prepare the garage door before installing the opener?",{"text":117,"@type":113},"Disable locks, remove any ropes connected to the door, and test balance by lifting the door about halfway and releasing it. Then raise and lower the door to check for binding or sticking; if it binds or is out of balance, contact a trained technician.",{"name":119,"@type":110,"acceptedAnswer":120},"What cautions does the manual emphasize during installation?",{"text":121,"@type":113},"Always call a trained door systems technician if the door binds, sticks, or is out of balance. Never loosen, move, or adjust garage door springs, cables, pulleys, brackets, or their hardware, since they are under extreme tension.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},653694,1793108758,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":29,"category_name":30,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":39,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":145},137441390410,"https://ap-avatar.wpscdn.com/avatar/2000252f4ab5702993?_k=1776741390130283984","The Chamberlain Group, Inc.  \n845 Larch Avenue  \nElmhurst, Illinois 60126-1196 [www.chamberlain.com](www.chamberlain.com)  \nGARAGE DOOR OPENER Model 248739  \nFor Residential Use Only  \nOwner’s Manual  \n■ Please read this manual and the enclosed safety materials carefully!  \n■ Fasten the manual near the garage door after installation.  \n■ The door WILL NOT CLOSE unless The Protector System® is connected and properly aligned.  \n■ Periodic checks of the opener are required to ensure safe operation.  \n■ The model number label is located on the left side panel of your opener.  \nTABLE OF CONTENTS  \nIntroduction 2-7  \nSafety Symbol and Signal Word Review .............. 2  \nPreparing Your Garage Door....................... 3  \nTools Needed .................................. 3  \nPlanning .................................... 4-5  \nCarton inventory ................................ 6  \nHardware inventory .............................. 7  \nAssembly 8-11  \nAssemble the Rail and Install the Trolley ............. 8  \nFasten the Rail to the Motor Unit ................... 9  \nInstall the Idler Pulley ............................ 9  \nInstall the Belt and Attach the Belt Cap Retainer ....... 10  \nSet the Tension ................................ 11  \nInstallation 11-27  \nInstallation Safety Instructions 11  \nDetermine the Header Bracket Location ............. 12  \nInstall the Header Bracket ........................ 13  \nAttach the Rail to the Header Bracket ............... 14  \nPosition the Opener ............................ 15  \nHang the Opener ............................... 16  \nInstall the Door Control .......................... 17  \nInstall the Battery Backup ........................ 18  \nInstall the Lights ............................... 18  \nAttach the Emergency Release Rope and Handle ...... 18  \nElectrical Requirements ......................... 19  \nInstall The Protector System® ................. 20-23  \nFasten the Door Bracket ...................... 24-25  \nConnect the Door Arm to the Trolley............. 26-27  \nINTRODUCTION  \nAdjustment 28-29  \nAdjust the UP and DOWN Travel Limits ............. 28  \nAdjust the Force ............................... 29  \nTest the Safety Reversal System ................... 30  \nTest The Protector System® ...................... 30  \nOperation 31-36  \nOperation Safety Instructions ..................... 31  \nUsing Your Garage Door Opener................... 32  \nUsing the Wall-Mounted Door Control .............. 33  \nCare of Your Opener ............................ 34  \nHaving a Problem? (Troubleshooting) .............. 35  \nDiagnostic Chart ............................... 36  \nProgramming 37-38  \nTo Add or Reprogram a Hand-Held Remote Control .... 37  \nTo Erase All Codes From Motor Unit Memory......... 37  \n3-Button Remotes .............................. 37  \nTo Add, Reprogram or Change a Keyless Entry PIN .... 38  \nRepair Parts 39-40  \nRail Assembly Parts ............................ 39  \nInstallation Parts ............................... 39  \nMotor Unit Assembly Parts ....................... 40  \nAccessories 41  \nNotes 42-43  \nRepair Parts and Service 44  \nWarranty 44  \nSafety Symbol and Signal Word Review  \nThis garage door opener has been designed and tested to offer safe service provided it is installed, operated, maintained and tested in strict accordance with the instructions and warnings contained in this manual.  \nWhen you see these Safety Symbols and Signal Words on the following pages, they will alert you to the possibility of serious injury or death if you do not comply with the warnings that accompany them. The hazard may come from something mechanical or from electric shock. Read the warnings carefully.  \nWhen you see this Signal Word on the following pages, it will alert you to the possibility of damage to your garage door and/or the garage door opener if you do not comply with the cautionary statements that accompany it. Read them carefully.  \nPreparing Your Garage Door  \nBefore you begin:  ","cbCair0ux21w9slW","https://ap.wps.com/l/cbCair0ux21w9slW","pdf",2380811,44,"English","# Introduction\n## Safety Symbol and Signal Word Review\n## Preparing Your Garage Door\n## Planning\n# Assembly\n## Assemble the Rail and Install the Trolley\n## Fasten the Rail to the Motor Unit\n## Install the Idler Pulley\n## Install the Belt and Attach the Belt Cap Retainer\n## Set the Tension\n# Installation\n## Determine the Header Bracket Location\n## Install the Header Bracket\n## Attach the Rail to the Header Bracket\n## Position the Opener\n## Hang the Opener\n## Install the Door Control\n## Install the Battery Backup\n## Install the Lights\n## Attach the Emergency Release Rope and Handle\n## Electrical Requirements\n## Install The Protector System®\n## Fasten the Door Bracket\n## Connect the Door Arm to the Trolley","[{\"question\":\"What is required for the garage door to close safely?\",\"answer\":\"The door will not close unless The Protector System® is connected and properly aligned. Periodic checks of the opener are also required to ensure safe operation.\"},{\"question\":\"How do you prepare the garage door before installing the opener?\",\"answer\":\"Disable locks, remove any ropes connected to the door, and test balance by lifting the door about halfway and releasing it. Then raise and lower the door to check for binding or sticking; if it binds or is out of balance, contact a trained technician.\"},{\"question\":\"What cautions does the manual emphasize during installation?\",\"answer\":\"Always call a trained door systems technician if the door binds, sticks, or is out of balance. Never loosen, move, or adjust garage door springs, cables, pulleys, brackets, or their hardware, since they are under extreme tension.\"}]","Chamberlain Garage Door Opener Model 248739 - Owner’s Manual | PDF",1792897088,111]