coalvet wrote:Hello, I have one of these stoves installed in my basement fireplace. I recommend a baro for this unit because it can get carried away when using coal. The internal damper should be open for all startups and closed down when your fire is established. Check all the door gaskets and the condition of the firebrick and grates. I recommend nut coal for this stove. You will have to shake this stove vigorously as the shaker grates don't move alot.
I doubt the damper is meant to completely shutoff the stove. Could you mean an internal damper as underlined in the quote above ?
I'm not familiar with such a rare stove here in the USA, but if there is such an internal damper, it is most likely for changing the pathway of the hot flue gases to help slow the gasses and extract more heat. It also causes a bit more resistance to flow so helps keep the stove from running too hot. Internal dampers that do this are nothing new.
In antique stoves they are called the "direct - indirect" damper. Sometimes, also called a "diverter". In old cook stoves and ranges they are labeled, "oven".
When that internal damper is opened for reloading fuel, the hot flue gasses go more directly from the firebox to the stove chimney collar. That allows a stronger draft to build up so that the new fuel gets burning more quickly. That stronger draft also helps prevent any chance of smoke leakage out of the stove when a loading door is opened.
When the new fuel is burning well, the damper can then be closed re-routing the flue gasses thorough the longer pathway, thus extracting more heat before the flue gasses reach the chimney.
Look inside your stove and see it there is another pathway the flue gasses can take if that internal damper is closed.
And pictures of the stove and it's insides would help us, to help you better.