{"product_id":"3l09-19-copeland-comfort-control-white-rodgers-board-mount-limit-control-175f-7-5","title":"3L09-19 Copeland Comfort Control (White Rodgers) Board Mount Limit Control 175F 7.5\"","description":"\u003ch1\u003e3L09-19 Copeland Comfort Control (White Rodgers) Board Mount Limit Control 175F 7.5\"\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\u003e3L09-19 Board Mount Limit Control (White-Rodgers \/ Copeland Comfort Control)\u003c\/strong\u003e is an automatic reset temperature safety switch designed to protect HVAC equipment, control boards, transformers, electric heating systems, and electrical compartments from overheating. Featuring a \u003cstrong\u003e175°F fixed open temperature\u003c\/strong\u003e and an extended \u003cstrong\u003e7.5-inch insertion length\u003c\/strong\u003e, this compact board-mounted bimetal limit switch interrupts the circuit when excessive temperatures are detected and automatically restores operation after cooling, providing dependable thermal protection for critical system components.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eCross-Reference\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e3L09-19\u003c\/li\u003e\n\u003cli\u003e3L0919\u003c\/li\u003e\n\u003cli\u003eL175F\u003c\/li\u003e\n\u003cli\u003eWhite-Rodgers 3L09-19\u003c\/li\u003e\n\u003cli\u003eCopeland Comfort Control 3L09-19\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 3L09-19\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 electrical 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 enclosures\u003c\/li\u003e\n\u003cli\u003eSafeguard electric heat assemblies\u003c\/li\u003e\n\u003cli\u003ePrevent temperature-related component failures\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\u003eElectric Heat Control Assembly\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003eTechnician Notes\u003c\/h3\u003e\n\u003cp\u003eThe 3L09-19 is an \u003cstrong\u003eautomatic reset, open-on-rise board mount limit control\u003c\/strong\u003e utilizing a compact bimetal sensing disc with a \u003cstrong\u003e7.5-inch insertion probe\u003c\/strong\u003e for applications requiring deeper temperature sensing. Under normal operating conditions, the contacts remain closed and open when the sensing surface reaches \u003cstrong\u003e175°F\u003c\/strong\u003e, interrupting the circuit to prevent overheating. Once temperatures fall below the reset threshold, the contacts automatically reclose and restore operation.\u003c\/p\u003e\n\u003cp\u003eThe extended probe design is commonly used in air handlers, electric heat packages, control compartments, and OEM HVAC equipment where standard insertion lengths are insufficient to accurately monitor component temperatures.\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 faults\u003c\/li\u003e\n\u003cli\u003eIntermittent operation\u003c\/li\u003e\n\u003cli\u003eRepeated thermal shutdowns\u003c\/li\u003e\n\u003cli\u003eElectric heat 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 the replacement temperature rating matches the original control.\u003c\/li\u003e\n\u003cli\u003eConfirm switch action is \u003cstrong\u003eOpen on Rise\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eVerify the 7.5-inch insertion length matches the application.\u003c\/li\u003e\n\u003cli\u003eSecure the sensing probe properly during installation.\u003c\/li\u003e\n\u003cli\u003eInspect terminals for corrosion or heat damage.\u003c\/li\u003e\n\u003cli\u003eTest switch continuity after installation.\u003c\/li\u003e\n\u003cli\u003eVerify 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\u003eElectric heat elements\u003c\/li\u003e\n\u003cli\u003eRelay condition\u003c\/li\u003e\n\u003cli\u003eVentilation around controls\u003c\/li\u003e\n\u003cli\u003eProbe insertion depth\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eControls, Temperature, 175 degrees F Fixed Open Temperature, 145 degrees F Fixed Close Temperature, Open on Rise Switch Action, Auto Reset, 7.12\" Insertion Length, Board Mounted 1\/2\" Bimetal Disc Limit Switch\u003c\/span\u003e\u003c\/p\u003e","brand":"Neuco","offers":[{"title":"Default Title","offer_id":45887391432770,"sku":"3L09-19","price":24.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1071\/8320\/files\/Screenshot2026-11-03131919_b387c8f2-c2d8-4726-9b5b-fd12bb61c83f.png?v=1793737416","url":"https:\/\/hvacpartstore.com\/products\/3l09-19-copeland-comfort-control-white-rodgers-board-mount-limit-control-175f-7-5","provider":"HVACpartstore","version":"1.0","type":"link"}