An intelligent ignition system

A review of the history of electrical resistance igniters (ERI) applications shows that it is the preferred ignition source for gas appliances with only one shortcoming-the ignitors can be easily fractured or broken if not handled carefully. Since this problem was recognized from the beginning, an improved-strength ignitor has been diligently sought. In 1987, a potential candidate was found and has since been undergoing development along with a new complementary burner control especially designed to maximize the ignitor's life. The new ignitor is called silicon nitride, so named because of the material used to house the tungsten electrical resistance heater element inside. The burner control is a microcomputer-based design with a special "learning routine" developed to bring the ignitor to the minimum temperature required to ignite gas for a particular appliance reliably under varying conditions of temperature, voltage, gas quality, and combustion air. The authors review the new ignitor and burner control in detail.