I'm confused how any unburned gases enter the reburn chamber at the top of my Jotul 3CB firebox. I have two air inlets/controls at the front of the unit that appear to provide combustion air into the front of the firebox. I observe the flames and they seem to flow up to the ceiling (which is actually the floor of the reburn chamber), then forward to slip past the gap at the top of the firebox and into the top part where the exhaust vent is located. The reburn chamber has a bunch of holes in the leading edges as if gases or exhaust flows though them somehow, but I do not understand how any of my unburnt gases actually get into this area to be reburnt?!?!