There are two ways to do without a flue: 1, cut a circular hole from the glass on the window. 2, use a water drill to play a flue in the wall. For households without a flue in the general design of the problem, it is now more common is to use a special rhinestone hole in the wall, the height should be moderate, unreasonable, if it will lead to discharge or smoke oil backflow, connected to the mouth of the pipe out of the pipe also have to use a bucket or something next to the smoke oil, or by then it is difficult to deal with the oil stains and very ugly.