OEM Lennox Heat Exchanger Assembly — 13X42

The genuine OEM Lennox 13X42 heat exchanger assembly (factory reference 612224-07) is the essential heat-transfer element in your Lennox gas furnace. It draws heat from the burner combustion and delivers it to the blower air stream, all while isolating hazardous flue gases from your indoor air. Engineered to precise Lennox tolerances, the 13X42 restores safe, full-capacity heating and a leak-free combustion path.

Common symptoms of a failing heat exchanger include cracks or splits in the metal, rust and corrosion, a wavering or yellow burner flame, soot buildup, unusual smells during heating, and increasing carbon monoxide readings. A compromised exchanger is a safety concern that warrants immediate replacement.

Why OEM matters: because the heat exchanger is a life-safety, combustion-critical part, its metallurgy, weld integrity, and dimensional accuracy cannot be compromised. The OEM 13X42 is manufactured to Lennox standards for an exact fit to the burner assembly and collector box, maintaining certification, warranty, and long-term reliability. Non-OEM substitutes risk improper sealing, early failure, and dangerous flue-gas leakage.