So I have got my 1956
AS Furnace completely restored, and it looks great. It's the tall style with a single 3 inch tube that runs from the bottom, where the burner is, to the top of the furnance housing. Has a lovered grill front. It apprears that there was only one pipe coming out of the top that goes throught the roof. The pipe is oval and made of .032 gage metal. To me that can't be safe! There is another oval lip that runs around the main collar that looks like another pipe could or would connect onto, almost making a double pipe. Does anyone have one of these furnaces, which I am sure someone does, and how many pipes are coming out of the top going throught the roof?
I tried to use a 3 inch pipe that I got from HD just to see if it would fit. Well it would with a little heating of the metal pipe. The pipe was about a 1/8 to small. I would like to put a double wall pipe in, but I don't think I will ever get it on the flange. Figured if I could make a double pipe of my own then I would need some type of sealent I would think, between the overlap of the metal were I would need to rivet it together. Anyone have any idea what kind of sealent would work and not melt from the exhaust heat, or would just using vent aluminum tape work to seal the seam?