{"product_id":"oem-lennox-heat-exchanger-assembly-57l29","title":"OEM Lennox Heat Exchanger Assembly — 57L29","description":"\u003cp\u003eThe genuine OEM Lennox \u003cstrong\u003e57L29\u003c\/strong\u003e heat exchanger assembly is the core combustion component of your Lennox gas furnace, transferring heat from burning fuel to the circulating air stream while keeping combustion byproducts safely separated from the air you breathe. Built to exact factory specifications, it restores your furnace to rated heating capacity and efficiency.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCommon failure symptoms:\u003c\/strong\u003e A failing heat exchanger often shows visible cracks or rust, produces a flickering or distorted burner flame, triggers repeated flame-sensor or limit-switch faults, or causes the furnace to short-cycle. Cracks can allow flue gases — including carbon monoxide — to mix with heated air, making prompt replacement a safety priority.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy OEM matters:\u003c\/strong\u003e Because the heat exchanger is both a safety and pressure-tested component, only a genuine Lennox \u003cstrong\u003e57L29\u003c\/strong\u003e assembly guarantees the correct metallurgy, weld integrity, and dimensional fit your furnace was engineered around. Aftermarket substitutes can compromise combustion sealing and void your equipment warranty. Choose the OEM part for reliable, code-compliant heating performance.\u003c\/p\u003e","brand":"Lennox","offers":[{"title":"Default Title","offer_id":63081070264691,"sku":"LNX-57L29","price":399.95,"currency_code":"USD","in_stock":true}],"url":"https:\/\/nationalhvacparts.com\/products\/oem-lennox-heat-exchanger-assembly-57l29","provider":"National HVAC Parts","version":"1.0","type":"link"}