{"product_id":"3l09-4-copeland-comfort-control-white-rodgers-board-mount-limit-control-150f","title":"3L09-4 Copeland Comfort Control (White Rodgers) Board Mount Limit Control 150F","description":"\u003ch1\u003e3L09-4 Copeland Comfort Control (White Rodgers) Board Mount Limit Control 150F\u003c\/h1\u003e\n\u003cstyle\u003e\na {\n    text-decoration: none;\n    color: #464feb;\n}\ntr th, tr td {\n    border: 1px solid #e6e6e6;\n}\ntr th {\n    background-color: #f5f5f5;\n}\n\u003c\/style\u003e\n\u003cdiv\u003e\n\u003cp\u003eThe \u003cstrong\u003e3L09-4 Board Mount Limit Control (White-Rodgers \/ Copeland Comfort Control)\u003c\/strong\u003e is an automatic reset temperature safety switch designed to protect HVAC equipment, electrical controls, and heating systems from overheating. Featuring a \u003cstrong\u003e150°F fixed open temperature\u003c\/strong\u003e, this compact \u003cstrong\u003eboard-mounted bimetal limit switch\u003c\/strong\u003e interrupts the circuit when excessive temperatures are detected and automatically restores operation after cooling, helping protect sensitive components from heat-related damage.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eCross-Reference\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e3L09-4\u003c\/li\u003e\n\u003cli\u003e3L094\u003c\/li\u003e\n\u003cli\u003eL150F\u003c\/li\u003e\n\u003cli\u003eWhite-Rodgers 3L09-4\u003c\/li\u003e\n\u003cli\u003eCopeland Comfort Control 3L09-4\u003c\/li\u003e\n\u003cli\u003e74T Series Board Mount Limit Control\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eDirect OEM\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhite-Rodgers 3L09-4\u003c\/strong\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eCompatible Brands\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eWhite-Rodgers\u003c\/li\u003e\n\u003cli\u003eEmerson\u003c\/li\u003e\n\u003cli\u003eCopeland\u003c\/li\u003e\n\u003cli\u003eYork\u003c\/li\u003e\n\u003cli\u003eColeman\u003c\/li\u003e\n\u003cli\u003eLuxaire\u003c\/li\u003e\n\u003cli\u003eGoodman\u003c\/li\u003e\n\u003cli\u003eRheem\u003c\/li\u003e\n\u003cli\u003eUniversal HVAC Applications\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eApplication\u003c\/h3\u003e\n\u003cp\u003eUsed in HVAC and heating equipment to:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eProtect control boards from overheating\u003c\/li\u003e\n\u003cli\u003eOpen safety circuits at elevated temperatures\u003c\/li\u003e\n\u003cli\u003eAutomatically restore operation after cooling\u003c\/li\u003e\n\u003cli\u003eProtect transformers and electrical compartments\u003c\/li\u003e\n\u003cli\u003ePrevent temperature-related component failures\u003c\/li\u003e\n\u003cli\u003eProvide automatic thermal protection\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eRelated Components\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBoard Mount Limit Switch\u003c\/li\u003e\n\u003cli\u003eSnap Disc Thermostat\u003c\/li\u003e\n\u003cli\u003eFurnace Control Board\u003c\/li\u003e\n\u003cli\u003eTransformer\u003c\/li\u003e\n\u003cli\u003eBlower Relay\u003c\/li\u003e\n\u003cli\u003eHigh Limit Control\u003c\/li\u003e\n\u003cli\u003eTemperature Sensor\u003c\/li\u003e\n\u003cli\u003eSafety Cutoff Switch\u003c\/li\u003e\n\u003cli\u003eElectrical Control Assembly\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eTechnician Notes\u003c\/h3\u003e\n\u003cp\u003eThe 3L09-4 is an \u003cstrong\u003eautomatic reset, open-on-rise board mount limit control\u003c\/strong\u003e utilizing a compact bimetal snap disc. Under normal operating conditions, the contacts remain closed and open when the sensing surface reaches \u003cstrong\u003e150°F\u003c\/strong\u003e, interrupting the circuit to prevent overheating. Once the temperature falls below the reset point, the switch automatically closes and restores operation.\u003c\/p\u003e\n\u003cp\u003eBoard-mounted limit controls are commonly used in furnace control compartments, blower sections, transformer protection circuits, and OEM HVAC equipment where compact, dependable overtemperature protection is required.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eCommon Symptoms of Failure\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eEquipment shuts down unexpectedly\u003c\/li\u003e\n\u003cli\u003eOpen safety circuit fault\u003c\/li\u003e\n\u003cli\u003eIntermittent operation\u003c\/li\u003e\n\u003cli\u003eRepeated temperature-related lockouts\u003c\/li\u003e\n\u003cli\u003eControl board overheating faults\u003c\/li\u003e\n\u003cli\u003eNo continuity through switch contacts\u003c\/li\u003e\n\u003cli\u003eFailure to reset properly\u003c\/li\u003e\n\u003cli\u003eElectrical compartment overheating\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eInstallation Tips\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eDisconnect power before servicing.\u003c\/li\u003e\n\u003cli\u003eVerify temperature ratings match the original component.\u003c\/li\u003e\n\u003cli\u003eConfirm switch action is \u003cstrong\u003eOpen on Rise\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eMount securely in the original location.\u003c\/li\u003e\n\u003cli\u003eInspect terminals for corrosion or heat damage.\u003c\/li\u003e\n\u003cli\u003eVerify airflow around electrical components.\u003c\/li\u003e\n\u003cli\u003eTest continuity after installation.\u003c\/li\u003e\n\u003cli\u003eConfirm proper operation through a complete heating cycle.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003chr\u003e\n\u003ch3\u003eRecommended Inspection Items\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eControl board condition\u003c\/li\u003e\n\u003cli\u003eTransformer temperature\u003c\/li\u003e\n\u003cli\u003eWiring harness connections\u003c\/li\u003e\n\u003cli\u003eElectrical terminals\u003c\/li\u003e\n\u003cli\u003eBlower motor operation\u003c\/li\u003e\n\u003cli\u003eAirflow restrictions\u003c\/li\u003e\n\u003cli\u003eVentilation around controls\u003c\/li\u003e\n\u003cli\u003eRelay condition\u003c\/li\u003e\n\u003cli\u003eEquipment operating temperatures\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003c\/div\u003e","brand":"Neuco","offers":[{"title":"Default Title","offer_id":45887390810178,"sku":"3L09-4","price":25.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1071\/8320\/files\/Screenshot2026-11-03085241.png?v=1793721172","url":"https:\/\/hvacpartstore.com\/products\/3l09-4-copeland-comfort-control-white-rodgers-board-mount-limit-control-150f","provider":"HVACpartstore","version":"1.0","type":"link"}