Used to reduce the diameter of galvanized round perimeter pipe. For all heating, air conditioning, and ventilation applications where rigid pipe is required. Stainless Steel Chimney Liner Reducer Connectors The stainless steel stove pipe reducer is used to connect an appliance to a chimney liner, chimney, or double-wall flue system. It can also be used to reline existing masonry chimneys. Use stove pipe cement or a caulking material designed for use with a wood stove. The cement must be able to withstand high temperatures. Clean the area with a wire brush before sealing to remove any rust or debris.