{"product_id":"oem-lennox-limit-switch-20j83","title":"OEM Lennox Limit Switch — 20J83","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e20J83\u003c\/strong\u003e limit switch is a high-temperature safety control that protects your furnace and home from overheating. Mounted on the heat exchanger or plenum, it monitors supply-air temperature and opens the circuit to shut off the gas valve if temperatures climb beyond a safe threshold — typically due to restricted airflow.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e A tripped or failing \u003cstrong\u003e20J83\u003c\/strong\u003e commonly causes the furnace to shut down on high limit, short cycle, or run the blower continuously with no heat. Because the switch often trips in response to a dirty filter, blocked ducts, or a weak blower, a limit fault can also flag an underlying airflow problem worth checking.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Each Lennox limit switch is calibrated to a precise trip and reset temperature matched to your furnace's heat exchanger and cabinet design. An aftermarket switch with the wrong set point can nuisance-trip or, worse, fail to open when it should. The factory \u003cstrong\u003e20J83\u003c\/strong\u003e ensures the exact temperature rating, correct mounting fit, and dependable overheat protection your Lennox system requires.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081113289075,"sku":"LNX-20J83","price":19.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-limit-switch-snap-disc-LNX-20J83.jpg?v=1783762476","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-limit-switch-20j83","provider":"National HVAC Parts","version":"1.0","type":"link"}