{"product_id":"oem-lennox-furnace-limit-switch-69w40","title":"OEM Lennox Furnace Limit Switch — 69W40","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e69W40\u003c\/strong\u003e limit switch is a high-temperature safety control that protects your Lennox furnace from overheating. Installed on the heat exchanger or supply plenum, it senses air temperature and interrupts power to the gas valve or heating elements the moment temperatures exceed the safe threshold, keeping your system operating within its designed limits.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e A failing \u003cstrong\u003e69W40\u003c\/strong\u003e often causes the furnace to short cycle, the blower to run non-stop, or the burners to fail to ignite at all. You may also see the control board flash a limit-open or high-limit fault code. These issues typically point to a switch that has drifted out of calibration or opened permanently.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Limit switches are calibrated to precise cut-out and cut-in temperatures matched to your specific Lennox model. An OEM \u003cstrong\u003e69W40\u003c\/strong\u003e ensures the exact trip point, mounting footprint, and terminal configuration the factory intended — avoiding the nuisance trips and safety compromises that come with mismatched aftermarket parts.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081097658739,"sku":"LNX-69W40","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-69W40.jpg?v=1783761149","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-furnace-limit-switch-69w40","provider":"National HVAC Parts","version":"1.0","type":"link"}