Unstable (single -walled) chimney pipes are used in existing brick channels for gigs. They can also be installed inside heated rooms as the initial elements of the chimney or for ventilation. A sleeve with stainless steel pipes in chimneys is carried out by putting or lowering them into existing brick channels. This is necessary so that the condensate formed from gases in the chimney is not absorbed into the brick walls, as this leads to the destruction of the entire channel. This is especially true for this problem of the channel section located on the street. To protect the chimney from destruction and ensure the long service life from the brick channel, wet smoke gases must be isolated. This is done using stainless acid -resistant chimney pipe.