My home was built in 1905, and I'm told the fireplace is coal-burning. We had vented gas logs installed a year ago, and have never used them for more than 20 minutes because of the awful smell that completely fills the house when they are burning. The dealer that installed the gas logs tells me that the logs themselves should not produce an odor. I've purchased a CO detector that doesn't pick up any kind of problem. Could something be burning on the inside of the chimney that is causing this smell? Is it even possible to use gas logs in a coal-burning fireplace? If not, what are my options for some sort of fire or embers - just for ambience, not heat? Any help is greatly appreciated!!