Can’t change fire color to black? I am trying to make an image with black fire against a white background but whenever I change the color ramp to black the fire just disappears, any help is appreciated.!
This is the node set up I have for the color (https://i.stack.imgur.com/qWJcw.jpg)
Try this node setup.  It's from Blender guru's fire tutorial.  I tested it out for you and it made black fire, so there you go.

I suggest watching the fire tutorial.  It gives a lot of good information on how to create good looking fire.  The video is titled How to "Render Fire in Cycles".