Does My Furnace Have a Crack in the Heat Exchanger?

UPDATE 12/08/25: I discovered that there is a groove in between the flame nozzles to allow gas to travel to the adjacent nozzle. Since there is only one igniter each nozzle lights up off the adjacent nozzle.

Furnace was installed in 1993.
See igniter replacement: https://www.youtube.com/watch?v=5bE9XtUluV4
A malfunctioning furnace can emit dangerous carbon monoxide which is an odorless poison. Get a professional HVAC technician to evaluate your furnace!

I think that it's a good idea to have a few carbon monoxide detectors around the house.

This video is for entertainment purposes only.