{"product_id":"oem-lennox-flame-rollout-switch-78l29","title":"OEM Lennox Flame Rollout Switch — 78L29","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e78L29\u003c\/strong\u003e flame rollout switch is a manual-reset safety limit that protects your Lennox furnace from dangerous flame rollout conditions. Mounted near the burner box, it constantly monitors for abnormal heat that occurs when flames escape the combustion chamber — typically due to a blocked heat exchanger, restricted flue, or failing draft inducer. When it senses an unsafe temperature, it immediately opens the circuit and shuts the furnace down to prevent damage and hazard.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e a furnace that repeatedly trips and won't restart until reset, no heat with a tripped rollout switch, short cycling on the burners, or a switch that stays open even after the cabinet has cooled. A switch that fails closed is even more concerning, since it removes a critical layer of safety protection.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e the Lennox \u003cstrong\u003e78L29\u003c\/strong\u003e is set to the precise trip temperature your furnace's safety design requires. Substituting a generic switch with a different rating can allow unsafe operation or cause nuisance shutdowns. Because this is a life-safety component, always install the factory-specified part to preserve proper protection and warranty coverage.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081095332211,"sku":"LNX-78L29","price":19.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-limit-switch-rollout-LNX-78L29.jpg?v=1783760984","url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-flame-rollout-switch-78l29","provider":"National HVAC Parts","version":"1.0","type":"link"}