Application: Double wall or triple wall air-cooled chimneys. (Collar Included) Vacu-Stack is the premier chimney cap (collar included) for solving common, wind-related chimney draft problems. Wind-induced downdraft can cause smoke to enter the living space when: Hills, mountains, tall trees, and or tall buildings are in the vicinity. Vacu-Stack also functions as a conventional chimney cap by protecting the chimney from rain, snow, debris, and animals. The optional stainless steel 1" mesh screen, used as a bird guard, will never rust and are available for either style of Vacu-Stack caps. The screen will assist against debris and animals from entering the chimney and will help contain sparks. See how the Vacu-Stack Chimney Cap works. Adapt your Vacu-Stack chimney cap to any standard masonry flue using this adapter. Sizing: Diameter A (Inside Flue Dimension) Diameter B Diameter C 6" 16" 14" 7" 16" 15" 8" 16" 18" 9" 16" 20" 10" 16" 21" SIZES: Custom sizes available up to 48". Please contact us for price, shipping time, and specifications.CHIMNEY TYPES: Double wall or triple wall round, air cooled. Installation Instructions: Vacu-Stack Mesh Screen Installation Instructions Step 1: Note the Spacers. The three spacers located on the underside of the TDW Air Cooled Vacu-Stack chimney cap maintain ventilation space between the bottom of the Vacu-Stack and top of the chimney. This is essential for uninterrupted air flow through cooling channels in air-cooled chimneys. Step 2: Fitting the Vacu-Stack inside the flue. Vacu-Stack chimney caps fit inside round metal and masonry flues. Press the pipe end of the Vacu-Stack into the flue until fit is snug. Step 3: Applying a Watertight Seal. Apply a thin layer of silicone caulking to seal joint between Vacu-Stack and top of chimney. The chimney silicone is an optional add-on for this product. If you are installing on rectangle or square flues, please visit the masonry adapter page.
