Newbie here. I am installing a wood stove insert with about 15' of 6" SS flex flue liner. I cut out the damper and will make a blockoff plate to seal around the liner. The firebox at one time had a gas fireplace installed and I am planning on using the hole in the firebox floor as an air intake. My question is should I have a way to control the amount of air flowing from the air intake, through the fireplace, and out the flue liner? The front of the insert (Pacific Energy) has a lever that says H, L. Will this be a decent setup for proper heating and draft? Thanks.