The Lennox 81W03 Ignition Control Board is a high-quality replacement part designed for use in Lennox gas furnaces. It plays a crucial role in the ignition process, controlling the furnace's spark ignition, gas valve, and flame sensing functions. This board ensures safe and reliable operation by monitoring ignition and shutting down the system if any irregularities occur, such as fail... https://www.partshnc.com/lennox-81w03-control-board