This replaced an insert. Full oval Duraliner system in the flue. I Installed an 8" oval X 8" round tee and had to jack up the liner system to match the rear flue outlet pipe on the Encore. Little bottle jack under the system and it went right up. Up on the roof to remount the system hanger. Mounted the 1' length transition pipe and coaxed the stove back and the pipe went together pretty easily...amazingly! Everything looks good. Now, I need only one more thing. WOOD 

I have my first fire today and it is just to cure things a bit. I will be installing a Tjernlund Air-Share to pump some heat into the back room. I tore out a complete gas furnace/AC system upon buying this place. In 45+ yrs in the business this place had the single most dangerous system I've seen. Stunning incompetence and lack of care for the people who were going to be blown up by the original installers.