OEM Lennox Heat Exchanger Assembly — 13X26

The genuine OEM Lennox 13X26 heat exchanger assembly (factory number 612222-07) is the essential combustion component of your Lennox gas furnace. It draws heat from the burners and transfers it to the air moving through your ductwork while keeping flue gases completely separated from that airstream. Produced to Lennox's precise specifications for materials, welds, and cell design, it preserves proper airflow, rated efficiency, and safe heating.

Typical indicators that a heat exchanger has failed include visible cracking or corrosion, a burner flame that wavers or discolors when the blower engages, soot buildup, combustion odors, or a furnace that repeatedly trips its high-limit safety and short-cycles. A cracked exchanger poses a carbon monoxide hazard, so replacement should not be postponed.

OEM is the right choice here. The authentic Lennox 13X26 / 612222-07 is built to survive the constant heat-and-cool stress cycles of your furnace without warping or fatiguing early, and it installs cleanly without the airflow and fit issues that plague aftermarket parts. Non-genuine substitutes can undermine safety, cut efficiency, and void your warranty. Restore your Lennox system with the exact factory replacement.