07 Dec What Is an Electronic Ignition System?
For decades, the way that natural gas-powered heaters ignited their burners was with a standing pilot light. People would keep the light burning through the heating season, so that whenever the gas jets for the burners turned on, the gas would immediately starting burning.
However, the standing pilot lights have now been replaced with electronic ignition systems. This makes furnaces safer and more energy efficient. Without a pilot light burning throughout the winter, a furnace needs to use much less gas.
How electronic ignition systems work
There are two basic types of electronic ignition systems in modern furnaces: hot surface ignition systems and intermittent pilot lights.
- Hot surface ignition: This is the more common of the two. It works similarly to the filament found in a light bulb. Electricity runs through a metal probe and causes it to heat up, even emitting a glow as it does so. Once the probe reaches the correct heat level, the gas valve opens up to allow gas to the burner, and heat from the probe ignites it. Because of the constant heating and cooling of hot surface ignition systems, they may eventually crack and need to be replaced. During maintenance, a technician will check if it is time to replace the igniter.
- Intermittent pilot: This system replaces the constantly burning standing pilot light with one that only turns on when necessary—thanks to an electric spark. The gas line to the pilot light only opens up when it’s necessary to ignite the burners. After the valve opens, the electric spark turns on the pilot light. When a flame sensor detects that the pilot is on, the gas valve to the burners opens, and the burners ignite as in an old standing pilot furnace. Once the burners are lit, the valve to the pilot light shuts off and the pilot goes out.
If you need repairs or replacements for a non-working electronic igniter, call for professionals!
Mid-State Air Conditioning and Heating offers repairs for furnaces in the Nashville, TN area. Our motto: “Fixed Right or It’s Free!”®