Hello All. Want to thank everyone who makes this website such a great source of information. Took the plunge today - there was a good sale - and we bought a Harman XXV. Installation is next week. Here's my situation and would greatly appreciate any advise. The Harman XXV replaces an old Consolidated Dutchwest wood stove - lasted 23 yrs but wanted something easier to work. The existing chimney has a 6" diameter stainless steel flue liner with a Saf-T Thimble thru the wall What is the best way to hook up the new stove to the existing chimney. The place where I bought the Harman is looking to vent the pellet stove using a 3" pipe, through 2 elbows, through a 3" x 6" pellet pipe adapter. I am not sure if they know the chimney is lined. Was wondering if I can take advantage of the existing steel liner to make the venting more insulated. A BIG problem we had with our old woodstove was lots of cold air leakage around the wall thimble into the room when the stove was not being used and also the thimble got very cold in the winter. Don't recall any problems with smoke in the room but we really did not use it that much. Looking forward to the new pellet stove but want to make sure we get a good installation that does not leak air into the house. Do I need to replace the Saf-T thimble?? Recaulk. Any help would be helpful. Thank you!!.