Has anyone had or know of a successful retrofit for a prefab fireplace. I have an older majestic prefab fireplace with a triple wall chimney. I have been toying with the idea of putting a pellet or gas burning device in it as it. I have given some thought to the Napoleon incert. The directions with that one allows it to be used even by building a false fireplace shell around it. My fireplace opening has a limit of 22 in in ht. I have a raised hearth in front of the opening. Years ago, when I didn't know any better, I had a small wood/coal combo stove sitting on the hearth and just ran a exhaust pipe up the fireplace chimney. While it worked, I have no idea if it was up to codes. Today, I'm not willing to take such risks. While in my current situation, with the pellet stove on the lower level, I am successfully heating my home, it would be nice to have a real fire in the livingroom space. At one point we had glass doors on it We burned wood with the glass closed to limit heat loss. For now, we have one ot those false electric log sets with the mirrors. Look fairly real, but just isn't it.