I just purchased my first home a few weeks ago and the previous owner installed a zero clearance fireplace in the living room. Other than being able to turn it on, I know nothing about these things. The fireplace is really nice, and I enjoy using it, but I would like to be educated, specifically on safety before I feel comfortable putting it on regularly. Since their is no exhaust to the outside of the house and it burns the oxygen in the room, how much of a concern should that be? Is Carbon Monoxide something I should worry about?? I've read about moisture, fogging up windows, and moisture causing mold to form in carpets. I have hard wood floors, does this minimize my concerns about moisture? In the handful of times that I've turned it on, I only leave it running for 45 mins to an hour, then turn it off. If it's used sparingly like that, would moisture form in that short of an amount of time? I hadn't noticed any previously. Is their any other negatives I should be aware of? What do I need to do to clean it? Thanks!