Unplug your machine. Removes screws on flame rod. To pull the rod out you will need to turn it as it is facing down and you'll need it to be facing horizontal. Be very careful not to break it. Crefully pull out. Just wipe it off. You may also be able to loosen the screws a bit and just jiggle it to make the carbon fall off. Be careful when retightening the crews. Do not over tighten them. You will strip the hole. It may be time to clean you heater or replace your burner ring if carbon is building up on your flame rod.