Question: I live in a condo built in 1974 with no gas and a double oven range that is flueless. It draws air from above and vents it out the back. The wall behind my kitchen stove is available and I could break through the wall and hook up to the unused flue, but I have some concerns: I am not sure if the flue can handle the heat, although I know an oven gets pretty hot. Could I insulate or line it? Answer: There is no telling exactly what that 7" flue was made for...but chances are that it IS NOT a regular class "A" chimney, which is what is needed for ANY appliance that burns wood. The only way to know for sure is to have it inspected by an expert, such as a certified chimney sweep or experienced fireplace/stove installer.