Jotul 600CB firelight- got home last nite opened the stove found some red coals, I was thinkin this ought to be easy. Loaded the stove opened the damper all the way, wadded up some news paper to heat the pipe up it felt cool to the touch. Lit paper closed door, then opened ash pan door to force draft. I do this to speed things up. Once I had good wood flame I closed the ash bin door and about 30 secs later I heard something, the best way I could describe it is a smoke explosion inside the stove. Anyhow smoke pushed from all the gasketed seams. I looked out and a big puff came out the pipe. Never had this happen before. My lit off procedure is the same as always. Stoved burned good all nite, any comments please...