I am getting ready to do my first sweep of my liner. I had the stove installed by someone else and I was not there when he did it so I dont really know how the liner is fastened to the insert. I hear everyone talk about how hard it is to move the brush up and down the liner. I am guessing the fit must be snug if you want to do get the gunk off. My question is, is it possible to pull the liner off the insert by sweeping it?