{"product_id":"oem-lennox-high-limit-switch-26g78","title":"OEM Lennox High Limit Switch — 26G78","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e26G78\u003c\/strong\u003e high limit switch is a temperature-sensitive safety control that monitors the heat exchanger and plenum temperature in your Lennox furnace. If the airflow is restricted or the unit overheats, the \u003cstrong\u003e26G78\u003c\/strong\u003e opens the circuit and shuts down the burners, preventing damage to the heat exchanger and reducing fire risk. It automatically resets once the temperature returns to a safe range.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e A failing high limit switch often causes short cycling (the furnace repeatedly firing and shutting off), no heat, or the blower running continuously. A switch that stays open indicates it has tripped or gone bad, while a stuck-closed switch defeats critical overheat protection.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e High limit switches are calibrated to a specific trip temperature. An incorrect or generic replacement can trip too early — leaving you without heat — or too late, allowing dangerous overheating. The factory-spec \u003cstrong\u003e26G78\u003c\/strong\u003e ensures the exact temperature calibration and terminal configuration your Lennox system was designed around.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081111421299,"sku":"LNX-26G78","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-26G78.jpg?v=1783761962","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-high-limit-switch-26g78","provider":"National HVAC Parts","version":"1.0","type":"link"}