Scott, Although I have a separate kiln devoted mainly to enameling, I
of ten use my burnout kiln for enameling and have never had a
problem. It is a Paragon programmable kiln which I purchased because
it is a multi-purpose kiln.
I have a wax drip tray that slides under a wire mesh. The flasks are
set on the mesh. The molten wax drips into the tray,and after a
period of time, when the wax has all melted, remove the tray with the
melted wax and continue the burnout.
If the walls of the kiln get blackened from the wax (rarely
happens), I just give them a coat of kiln wash.
Never never had a problem using the same kiln for enameling.