This morning I woke up the power going off and on then off for good. The stove fired up then as soon it lost power smoke starting pouring all into the house from the heat exchangers. I had no idea what to do to stop it. When I opened the door the fire lit back up and burned the pellets off. I have a vent out the side of the house then goes vertical about 4 ft. My vent pipes are clean because I just cleaned them last week. What should you do in this situation to stop the smoke pouring in?