Hello all I have a question, I have a Mendota ML47 fireplace installed in my house but I can't even use it cause after 1 1/2 hr of running my house smells and my family and I get headaches. I thought that it could be CO so I went and bought a CO detector the plug in version and after installing it and running the fireplace nothing. So it isn't CO the smell. My neighbor has a mendota fireplace not like mine different model but his works fine no smell. The company even exchanged it and it worked fine for 1 winter season and now it is smelling again. What could be the reason for this damn smell???