Ok I got my K100 from FT today. Tried several of my tanks on it (Vivi Nova, Evod, etc) and everything was great. Then I decided to try out the cartomizer and drip trip that came with it. It got hot quick! Dumped the battery out and it, and the K100, was hot to the touch. Let them cool down, put the battery back in and then tried again....with tanks. Everything seemed fine. Any idea what caused that?