I am new to all of this...So I am sure some of these questions have been answered 100 times but I love fireplaces...and am looking to install an insert in my home. I have been using my existing fireplace on the regular when cold enough and can heat my house up into the 60s with ease, but it eats wood quickly. Id like to get something together that is alot more efficient. Wife and I bought a house few months ago....Smallish split entry approx 1250sq ft north of Pittsburgh, PA.. The home is a 1980s build with masonry fireplace brick chimney that is lined. Opening on the fireplace is 36"W x 24"H X 22"D... I have been reading on hearth.com for a bit but have been holding back from posting, but figured id ask some advice. I am not looking to break the bank as i know there are some very nice quality stoves out there. I am looking to install a fireplace insert as a supplemental heat source for the home. The house is currently heated with heating oil, and while the cost is not crazy at the moment, i know that can fluctuate. We have 5 acres and another empty 10 acres around us....Its all wooded and we have basically an almost endless supply of good burning hard wood.... I am planning on taking out the steel insert in the current fireplace, removing the flue, sweeping the current chimney and running a new stainless liner up the chimney. Do I need more than double walled and or flex duct?? From there I have been looking at inserts...I like the look of the Osburns but like the price of the Vogelzang "The Colonial" on Northern Tool and A Century I found that all seem to fit the opening with ease...Trying to keep the cost around $2000 for everything. I'll be doing the install.... Next question is I have 4 vents around my fireplace...Its a heatalator system that hardly works...the fans spin but very little air movement comes from them...Is there a way I can fill these or do I need to leave them?