{"product_id":"lennox-73w19-genuine-oem-limit-control-switch-155-f-open-125-f-close-102857-06","title":"Lennox 73W19 Genuine OEM Limit Control Switch 155°F Open \/ 125°F Close 102857-06","description":"\u003ch1\u003eLennox 73W19 Genuine OEM Limit Control Switch 155°F Open \/ 125°F Close 102857-06\u003c\/h1\u003e\n\u003cp\u003eThe \u003cstrong\u003eLennox 73W19\u003c\/strong\u003e (Model 102857-06) is a critical safety component designed for Lennox high-efficiency gas furnaces. Known as a \u003cstrong\u003ePrimary Limit Control\u003c\/strong\u003e, this \"STILT\" style sensor monitors the temperature of the heat exchanger. Its primary role is to protect your home and equipment by cutting power to the gas valve if the internal furnace temperature exceeds safe operating limits.\u003c\/p\u003e\n\u003cp\u003eThis specific sensor is factory-calibrated to \u003cstrong\u003eactuate (open) at 155°F\u003c\/strong\u003e and automatically \u003cstrong\u003ereset (close) at 125°F\u003c\/strong\u003e. Featuring a distinct \u003cstrong\u003eyellow sleeve\u003c\/strong\u003e for easy identification and a \u003cstrong\u003e5-inch Overall Length (OAL)\u003c\/strong\u003e, it is engineered for a \"Left Orientation\" mount. Choosing a \u003cstrong\u003eGenuine OEM Lennox replacement\u003c\/strong\u003e ensures the thermal response time matches your furnace's safety profile exactly, preventing dangerous overheating or nuisance tripping.\u003c\/p\u003e\n\u003ch2\u003eKey Features and Function:\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision Thermal Protection:\u003c\/strong\u003e Automatically shuts down the heating cycle at 155°F to prevent heat exchanger damage or fire hazards.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAutomatic Reset Logic:\u003c\/strong\u003e Once the plenum temperature drops to 125°F, the switch closes to allow the furnace to resume normal operation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSTILT Design Integration:\u003c\/strong\u003e The 5-inch probe reaches deep into the airflow path for accurate real-time temperature monitoring.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor-Coded Identification:\u003c\/strong\u003e Features a yellow sleeve, ensuring technicians can verify the correct temperature range at a glance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eProduct Details and Key Specifications:\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 73W19 (Model: 102857-06)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Lennox (Genuine OEM)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Type:\u003c\/strong\u003e High Limit Control Switch (STILT Style)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOpen Temperature:\u003c\/strong\u003e 155°F (68°C)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClose\/Reset Temperature:\u003c\/strong\u003e 125°F (52°C)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOrientation:\u003c\/strong\u003e Left Hand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProbe Length:\u003c\/strong\u003e 5\" OAL (Overall Length)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSleeve Color:\u003c\/strong\u003e Yellow\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShipping Weight:\u003c\/strong\u003e 0.2 lbs\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003e🛠️ HVAC Depot Pro Tip: Airflow \u0026amp; Tripping\u003c\/h2\u003e\n\u003cp\u003eIf your new 73W19 limit switch continues to trip (\"open\"), the problem is rarely the switch itself. A limit trip usually indicates \u003cstrong\u003erestricted airflow\u003c\/strong\u003e. Before replacing the part, check for a dirty air filter, blocked return vents, or a failing blower motor. A \"tripped\" limit is often the furnace's way of telling you it can't breathe.\u003c\/p\u003e\n\u003ch2\u003eCross-Reference \u0026amp; Compatibility:\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003e73W19\u003c\/strong\u003e is a direct OEM replacement for the following part numbers:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLennox Numbers:\u003c\/strong\u003e 102857-06, 73W1901, L155-30F\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndustry Cross-Refs:\u003c\/strong\u003e 36TX11, 20352\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eExtensive Model Compatibility List:\u003c\/h2\u003e\n\u003cp\u003eNote: Use 'CTRL+F' to search for your specific model:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEL Series:\u003c\/strong\u003e EL296UHV, EL296DFV, EL195UH, EL195E\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSLP Series:\u003c\/strong\u003e SLP98UHV, SLP98DFV\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eG Series:\u003c\/strong\u003e G61MPV, G71MPP, G40UH, G50UH\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eML Series:\u003c\/strong\u003e ML195UH, ML180UH\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":52451505111403,"sku":"66255141843","price":65.49,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0922\/9683\/9531\/files\/80K2601_249ae4e8-717f-4340-8e56-08c329ee55d9.jpg?v=1761770075","url":"https:\/\/tophvacparts.com\/products\/lennox-73w19-genuine-oem-limit-control-switch-155-f-open-125-f-close-102857-06","provider":"HVAC Parts and Equipment Depot Open To Homeowners and Contractors","version":"1.0","type":"link"}