Description
The Lennox 99W42 is a durable aluminum heat exchanger assembly engineered for reliable heat transfer and long-term performance. Featuring a 5-tube configuration, this 108 K BTU/hr unit is commonly used in Lennox KGA, KGB series packaged gas-electric furnaces, rooftop units, and air handling systems. It is the direct replacement for models like 15W85 and LB‑112079B.











