Hey all. I'm brand new here. Nice to be here. Favor. I have a Heritage Energy Systems Inc. Wood Stove. Model #24 S. I'm not sure how to exactly use it optimal. As ypiou can see in the photos, it has a side handle that opens and closes a rectangular flu inside. Is it to make it more efficient? I can't get my stove to stay hot enough without having the door slighly open. I love the fan on the back that blows the hot air through a rear double wall and outward. Anybody else have one and have any tips on operating it? Thanks in advance!