Maybe a dumb question, but any reason why you couldn't just use dry erase markers directly on a smooth white chest freezer rather than painting it with chalk board paint or some other option? Anything about appliance surface that would make the dry erase markers permanent?
It should work fine but test it somewhere out of sight with different colored markers. Red or blue tend to stain the image onto some surfaces with prolonged exposure. These "labels" will be there for however long the kegs last which could be a few weeks.
I do it so much, that I actually make drawings and notes on my fridge in the garage. The green seems to be the hardest to wipe, but the spray cleaner (or just alcohol or Windex) wipes it right off.
Go for it!
My fermentation fridge has black plastic covering the doors and i cleaned them with glass cleaner than sprayed them down with white board restorer\cleaner solution before writing on it with dry erase markers. seems to work great. i did have to buy neon colored markers to be visible on the black surface though.
I was contemplating chalkboard paint when I saw this thread, then immediately went to amazon and ordered dry erase markers. It seems so obvious I don't know why I hadn't thought of it. Thanks for the idea!