How To Reset Furnace Pilot Light. If the furnace has a sealed pilot compartment, you may see a red button for piezoelectric spark ignition, and if so, press this button repeatedly until the pilot starts. Pilot light if you furnace has a standing pilot light, make sure that it’s lit.
Locate the reset button on the furnace and press it to reset the furnace. First, you’ll need to start the process by making sure the pilot light is off. A gas furnace that's on the fritz as a result of the pilot light being out means your home isn't getting the kind of heat it needs.
If you turned off the power, turn it back on.
This should relight the pilot flame. Relight the pilot by holding a lit match or lighter in front of the pilot flame jet. After that, press the reset button for a while and use a long lighter flame near the opening of the pilot light. This should light the furnace pilot light.