The hot surface igniter is the component that lights the gas in your furnace every heating cycle. When the thermostat calls for heat, the control board sends voltage to the igniter, which glows red-hot within seconds to ignite the gas flowing from the burners. Igniters are fragile ceramic components that crack from thermal stress over time, making them one of the most common furnace repairs.
Silicon carbide igniters are the original technology found in older furnaces. They are flat, rectangular, and relatively fragile. Silicon nitride igniters are the modern upgrade, offering faster heat-up times, greater durability, and resistance to cracking. Silicon nitride igniters can often replace silicon carbide units when the voltage and mounting style match. Most universal igniters at National HVAC Parts are silicon nitride for maximum reliability.
Flat igniters are the most common style, used in the majority of residential furnaces from Carrier, Bryant, Payne, and ICP. Round igniters feature a spiral or fork-shaped element and are found in some Rheem, Ruud, and Trane models. Mini igniters are compact versions used in tight burner assemblies. Always match the shape and mounting bracket to your existing igniter for a proper fit.
OEM igniters carry the original manufacturer part number and are guaranteed to fit your specific furnace model. Universal igniters are designed to replace hundreds of OEM part numbers across multiple brands. A single universal silicon nitride igniter can often replace 150 or more OEM numbers. Universal igniters from National HVAC Parts include all necessary mounting hardware and wiring connectors.
The most common symptom is the furnace not lighting. You may hear the inducer motor and blower running, but no flame appears. Other signs include visible cracks in the ceramic element, the igniter glowing dimly or unevenly, the furnace locking out after multiple failed ignition attempts, or intermittent heating where the furnace sometimes lights and sometimes does not.
Look for the existing igniter part number printed on the ceramic body or check your furnace manual. Use our Look Up by Model Number tool above to find the exact OEM replacement, or use Shop by Specs to browse by material type and shape. Every order placed before 3 PM CST ships same day from National HVAC Parts.