The Resideo Q3400A1008 is a hot surface pilot igniter and flame-sensing assembly designed for SV 18-inch pilot applications in compatible gas-fired HVAC systems. It operates by electrically heating the igniter element until it reaches ignition temperature, allowing the pilot gas to ignite, while the flame sensor confirms proper flame establishment. This component is used in compatible... https://www.partshnc.com/q3400a1008-resideo-hot-surface-pilot-igniter-sensor-assembly-18-cable