New gas fireplace conversion - help?

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New Member
Feb 22, 2016
Boise, ID
Hello and thanks in advance for letting me join this excellent resource.

I have a 1906 wood burning fireplace that I would like to convert to a vent-free gas log system (no interest in burning wood). Chimney sweep said the fireplace is pretty much shot, air is escaping 1/2 way up, not making it to the top of chimney, the flue is completely rotted, and there is a negative draft coming down, so I'd like to completely close it off. Mostly because it makes my living room smell like smoke on certain days spending on the temp/wind conditions, but also because is also a massive cold draft. I'd like to seal the top (with a mortar/caulk and galvanized sheeting) and also also create a block off plate above the actual fireplace. Here is the question - is this the best idea, and, at this point would it make sense to create a small vent pipe even for the ventless gas logs to make double sure of proper venting? And can I then have a tiny flue in a 3" - 4" pipe that is essentially an extra vent system so I never have to worry about keeping a window open for humidity to escape? I have done the vent free calculation and I am more than fine with cubic space, but I still don't like what I read about the vent free systems to fully commit. Your advice is appreciated!
You'll get differing opinions here, but, I have a absolutely no concern with the safety of vent free appliances. I have them in my own home and, as long as they are installed and operated to manufacturer specification, I am comfortable with the technology.
Seal that crappy chimney off and utilize the firebox with a vent free log set.
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