I guess I am a bit puzzled by your comments. Since I have not installed a dryer in a new installation before, and only worked on them after installation, I was under the impression that the venting of the burner and the exhausted air that is used to dry the clothes are combined, and sent up a single pipe (typ.). As you can read in another follup elsewhere in another thread from my original post, I am planning to route the combined exhaust via a temporary setup out a door left adjar, or through a removed lite in the door glass. FYI it is a single floor duplex, and very old. I doubt these girls will live there that long, so investing in research on flue capacities, and any exotic solutions are not worth it. The electric service is an antique, so no electric dryer option. Not by me, anyway. I would end up rewiring the entire place. By the way, thanks for all the helpful comments.