This so called vaporizer, sold on ebay, does not heat over 200F. In personal ebay communication, Seller said to raise the voltage to get the temperature where it needs to be and to use 'pure' oxalic acid which supposedly sublimates at lower temperatures. I asked him to change his description, he said he would. In the process, time expired for a dispute (my bad). I'm stuck with it, you don't have to be stuck with it.
WARNING: This device is junk.