Professionals enter the flue to clean it. For those who cannot enter the flue manually because the smoke outlet is narrow, or cannot be cleaned because the flue is too narrow to be reached by manual, but there are major hidden dangers, they can use high-pressure water gun to clean it with cleaning agent or caustic soda, without leaving any dead ends. If hydrochloric acid is used, it must be washed with clear water immediately. This method is the most thorough and effective cleaning method, but it is difficult to construct and requires a large number of workers.

The cleaning scheme is: according to the actual situation of the flue, technicians calculate that a section of flue should be dismantled at regular intervals and extended in two directions to ensure thorough cleaning and quality.

2 Opening method This method is relatively easy and relatively low in cost compared with disassembly method, but the cleaning effect is relatively poor.

The specific method is: technicians calculate the interval distance, position, size and number of holes to be opened, and clean the flue through these holes. Finally, each hole is sealed.