I have tried putting aluminium foil about 3 inches out from around burner, but that seemed to exacerbate the problem. I think it helped the insulate the area under the foil. It seems like I am ruining the stove. Is there anyway to prevent this from happening? I know I can get a burner for outside, but I would really rather brew inside the house. Especially in the winter.
I'm a little late to this question, but I thought one solution might be to put down a layer of fiberglass fabric, the kind that is impregnated with epoxy to form fiberglass hulls and such. In its fabric form it is easy easy to lay down underneath and around the burner, non-conductive (if you have electric burners), impervious to heat, and an excellent insulator that should block most of the radiant heat coming off the burner.
I wonder if this foil insulation would help: http://www.lowes.com/pd_13353-56291-ST16025_4294858104_4294937087?productId=1014123&pl=1¤tURL=/pl_Foil%2BInsulation_4294858104_4294937087_ It seems like you could just lay a sheet over the enamel while you boil. Of course, the first time you use it, you should probably babysit it to make sure it doesn't catch fire!